Fast Facts:

Summary:  A well-organized and long-lived complex of storms produced widespread severe wind damage across Iowa, northern Illinois, and northern Indiana during the day on Monday, August 10. Much of this severe wind was significant (75+ mph winds) resulting in many downed trees, several toppled-over semi trucks, and many communities receiving at least some minor structural damage. Within the broader area of severe winds, 15 tornadoes were confirmed across northern Illinois and northwest Indiana. ​Several tornadic circulations developed within the main line of thunderstorms, and these accounted for 13 tornadoes across northern Illinois and northwest Indiana. In addition, a lone supercell that was subsequently absorbed into the main line produced two tornadoes in and around the Rockford area, bringing the total number of tornadoes for this event to 15. As it stands at this time, since 1950, this is tied for the 2nd highest number of tornadoes to occur on a single calendar day in NWS Chicago`s area of responsibility, and the most to occur on a single calendar day in the month of August. Preliminary August 10th numbers: Over 700 reports of severe wind speeds (58+ mph) or wind damage from the Nebraska/Iowa border, across Iowa, northern Illinois, and northern Indiana. This was a high end, once-a-decade type event for the area. Over 150 of the wind reports are from all of northern Illinois and northwest Indiana. 12 injuries were reported in the NWS Chicago CWA, 5 being in Forreston, IL, 1 in Peru, IL, 3 in Matthiessen State Park near Utica, IL, 1 in Lake Villa, IL, 1 in Lake Station, IN, and 1 in Hammond, IN. In the NWS Chicago County Warning Area, 15 tornadoes were confirmed, which includes portions of northern Illinois and northwest Indiana. As of this time, this count ties August 10, 2020 with June 22, 2016 as the single calendar day with the 2nd most tornadoes within our county warning area (behind the 6/30/2014 "Double Derecho" event). In total, the derecho produced 20 confirmed tornadoes across Illinois, Wisconsin, and Indiana. The tornadoes include an EF-1 tornado in Rogers Park, Illinois (a north-side neighborhood of Chicago), that moved out over Lake Michigan and became a waterspout. This was the first tornado in the city of Chicago since September 3, 2018 (EF-0). This was the first F-1/EF-1+ tornado in the city of Chicago since March 12, 1976 (F-2) that clipped the far northwest side of the city, roughly near O'Hare Airport and Edison Park. Derecho Facts:  This complex of storms was known as a derecho. A derecho produces a swath of particularly damaging thunderstorm winds (specifically, wind gusts of at least 58 mph along most of its length with several well-separated 75 mph or greater gusts) over an area at least 250 miles long. These are primarily classified as straight-line winds rather than tornadic. Even so, wind speeds in a derecho can exceed 100 mph which is equivalent to that of an EF-1 tornado but over a vastly larger area than a tornado would impact. Tornadoes can also be embedded within derechos and produce concentrated areas of even more intense damage. Derechos develop in an environment with very warm and moist air at the surface, colder air aloft, and moderate to strong winds at upper levels of the atmosphere. Northern Illinois and northern Indiana have long been known as a corridor of enhanced derecho activity, as shown in this graphic from a published paper by Guastini & Bosart (2016) titled "Analysis of a Progressive Derecho Climatology and Associated Formation Environments". Q&A on Derechoes Understanding a Damaging Wind Thunderstorm Complex Derecho climatology from 1996-2013 by Guastini and Bosart (2016).   Preparedness:  Despite the massive coverage and impressive intensity of the wind damage, there were a limited number of serious injuries. This speaks to the effort of our partners including fellow meteorologists in the weather enterprise effectively communicating the threats and action needed to be taken, as well as emergency management and law enforcement for their preparedness efforts beforehand and assistance efforts immediately after. Of course it also means that many public citizens heeded the threat and the warnings, as well as communicated them to their family and friends (being a "Force of Nature!"). For more on severe weather preparedness, see here.  The Forecast:  Forecast confidence increased markedly Monday morning that severe weather was likely across northern Illinois and northwest Indiana that afternoon. At NWS Chicago, our messaging accordingly increased, and we issued a Situation Report (briefing) for our partners at 9:15 a.m. and held a conference call with them near 12 p.m. The office also issued eight Severe Thunderstorm Warnings and six Tornado Warnings. Here is some of the forecast information from the NWS Storm Prediction Center (SPC) and NWS Chicago: SPC Day 1 Severe Thunderstorm Outlook issued at 7:16 a.m., Aug. 10. NWS Chicago Weather Story graphic issued at 9:00 a.m., Aug. 10. SPC Day 1 Severe Thunderstorm Outlook issued at 10:57 a.m., Aug. 10. NWS Chicago Weather Story graphic issued at 11:15 a.m., Aug. 10. More on the severe weather outlook categories can be found here. Severe Thunderstorm Watch (issued at 11:25 a.m., Aug 10 through 7 p.m. This was a rarely issued Particularly Dangerous Situation Severe Thunderstorm Watch due to the likelihood of widespread significant wind damage. NWS Chicago Weather Story graphic illustrating forecast timing of severe winds, issued at 12:00 p.m. Aug. 10.

Storm Reports

Regional Storm Reports			Local Storm Reports
For interactive maps of storm reports, visit the Storm Prediction Center Storm Reports page.

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHICAGO IL
1255 PM CDT FRI AUG 14 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0215 PM     TSTM WND GST     FORRESTON               42.13N 89.58W
08/10/2020  E100 MPH         OGLE               IL   NWS STORM SURVEY

            *** 5 INJ ***
            UPDATES PREVIOUS TSTM WIND DMG REPORT FROM
            FORRESTON. SEVERAL TRAILERS WERE DAMAGED OR
            DESTROYED. SIGNIFICANT DAMAGE WAS DONE TO A
            METAL BUILDING NEAR THE BP GAS STATION WITH
            ASSOCIATED DEBRIS BLOWN TOWARD THE
            NORTHEAST. WIDESPREAD TREE DAMAGE WAS ALSO
            NOTED. ALTOGETHER, THE DAMAGE WAS CONSISTENT
            WITH STRAIGHT LINE WINDS AROUND 100 MPH.

0225 PM     TSTM WND DMG     HARMON                  41.72N 89.55W
08/10/2020                   LEE                IL   TRAINED SPOTTER

            SEVERAL BRANCHES DOWN. EXTERIOR SIDE OF
            HOUSE PEELED AWAY.

0239 PM     TSTM WND GST     4 SSW DIXON             41.78N 89.50W
08/10/2020  M92 MPH          LEE                IL   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 92 MPH WIND
            GUST JUST SOUTH OF DIXON AT 2:39 PM. 20-30
            MINUTES OF WINDS GUSTING MORE THAN 50MPH.

0240 PM     TSTM WND DMG     2 SE ROCKFORD           42.25N 89.07W
08/10/2020                   WINNEBAGO          IL   TRAINED SPOTTER

            LARGE LIMB DOWN. TIME ESTIMATED BY RADAR.

0240 PM     TSTM WND DMG     2 NW HILLCREST          41.97N 89.09W
08/10/2020                   OGLE               IL   BROADCAST MEDIA

            LARGE TREE LIMB DOWN. TIME ESTIMATED BY
            RADAR.

0240 PM     TSTM WND GST     1 NE CEDAR POINT        41.27N 89.11W
08/10/2020  M91 MPH          LA SALLE           IL   TRAINED SPOTTER

            TREE DAMAGE, POWER LINES DOWN, 2 SEMIS
            OVERTURNED, SNAPPED TRAFFIC SIGNS, AND ROOF
            DAMAGE TO HOMES REPORTED. TIME ESTIMATED BY
            RADAR.

0243 PM     TSTM WND DMG     2 N PERU                41.35N 89.12W
08/10/2020                   LA SALLE           IL   BROADCAST MEDIA

            *** 1 INJ ***
            CORRECTS PREVIOUS TSTM WND DMG REPORT FROM 2
            N PERU FOR INCLUDING ONE INJURY THAT WAS THE
            TRUCK DRIVER, AS REPORTED BY AREA RADIO
            STATION WLPO. SEMI TRAILER BLOWN OVER ON IL
            251. TIME ESTIMATED BY RADAR.

0245 PM     TSTM WND DMG     3 SE LOVES PARK         42.28N 89.03W
08/10/2020                   WINNEBAGO          IL   PUBLIC

            IN ROCKFORD, LOTS OF DOWNED TREES, POWER
            LINES AND POLES, AND FENCES NORTHEAST OF THE
            AREA FROM NEAR THE NORTH ALPINE AND GUILFORD
            INTERSECTION THRU SHAW WOODS TO THE MULFORD
            RD AND SPRINGBROOK ROAD INTERSECTION AND
            ACROSS ROCK VALLEY COLLEGE.

0245 PM     TSTM WND DMG     1 ESE ROCKFORD          42.26N 89.07W
08/10/2020                   WINNEBAGO          IL   PUBLIC

            1 FOOT DIAMETER BRANCH DOWNED. WINDS
            ESTIMATED AT 60 MPH. TIME ESTIMATED BY
            RADAR.

0245 PM     TSTM WND DMG     ROCKFORD                42.27N 89.09W
08/10/2020                   WINNEBAGO          IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS WIDESPREAD TREE
            DAMAGE IN ROCKFORD. MEDIUM TO LARGE BRANCHES
            AND TREES SNAPPED.

0245 PM     TSTM WND GST     MENDOTA                 41.55N 89.12W
08/10/2020  E80 MPH          LA SALLE           IL   NWS EMPLOYEE

            CORRECTS PREVIOUS TSTM WND GST REPORT FROM
            MENDOTA. WIND GUSTS TO SEVERE LIMITS WERE
            FREQUENT FOR 30 MINUTES AFTER THEY STARTED.
            THE PEAK GUST WAS ESTIMATED TO BE AROUND 80
            MPH. SEVERAL LARGE TREES DOWNED IN TOWN.

0246 PM     TSTM WND DMG     2 NNE MENDOTA           41.58N 89.10W
08/10/2020                   LA SALLE           IL   PUBLIC

            THUNDERSTORM DOWNED LARGE TREE ON THE
            PROPERTY OF A MANUFACTURED HOME AND IMPALED
            A SMALL BRANCH FROM THIS INTO ONE OF THE
            WALLS. TIME ESTIMATED FROM RADAR.

0247 PM     TORNADO          2 SW ROCKFORD           42.26N 89.12W
08/10/2020                   WINNEBAGO          IL   NWS STORM SURVEY

            A VERY BRIEF TORNADO WITH PEAK WINDS OF 75
            MPH AND PATH LENGTH OF 1.5 MILES TOUCHED
            DOWN NEAR THE INTERSECTION OF PIERPONT AVE
            AND MONTAGUE ROAD AND CONTINUED NORTHEAST
            INTO THE SOUTHWEST SIDE OF ROCKFORD. THE
            TORNADO ENDED NEAR THE INTERSECTION OF
            FERGUSON AND LOOMIS STREETS. ALL DAMAGE WAS
            TO TREES ALONG THE TORNADO PATH.

0247 PM     TORNADO          4 SE MACHESNEY PARK     42.31N 88.98W
08/10/2020                   WINNEBAGO          IL   NWS STORM SURVEY

            AN EF-1 TORNADO WITH PEAK WINDS OF 100 MPH
            AND PATH LENGTH OF 9.2 TOUCHED DOWN JUST
            NORTH OF ROCKFORD COLLEGE AND TRAVELED
            NORTHEAST INTO CALEDONIA. SIGNIFICANT TREE
            DAMAGE CONSISTENT WITH EF-1 SPEEDS OCCURED
            IN A LOCALIZED AREA NEAR ROCK VALLEY COLLEGE
            WITH SPORADIC DAMAGE THEREAFTER. THIS
            TORNADO WAS PRODUCED BY A SUPERCELL
            THUNDERSTORM WHICH HAD ALREADY PRODUCED A
            BRIEF TORNADO UPSTREAM.

0248 PM     TSTM WND DMG     CRESTON                 41.93N 88.96W
08/10/2020                   OGLE               IL   TRAINED SPOTTER

            LARGE TREE LIMBS DOWNED. TIME ESTIMATED BY
            RADAR.

0250 PM     TSTM WND DMG     3 E LOVES PARK          42.31N 89.00W
08/10/2020                   WINNEBAGO          IL   BROADCAST MEDIA

            LARGE TREES SNAPPED AND LARGE LIMBS DOWN ON
            THE ROCK VALLEY COLLEGE CAMPUS. TIME
            ESTIMATED BY RADAR.

0252 PM     TSTM WND DMG     4 ESE MACHESNEY PARK    42.32N 88.98W
08/10/2020                   WINNEBAGO          IL   PUBLIC

            FARM AND FLEET ON EAST RIVERSIDE ROAD IN
            LOVES PARK LOST A GOOD PORTION OF ITS ROOF.

0253 PM     HAIL             4 NNW CHERRY VALLEY     42.29N 88.98W
08/10/2020  E1.00 INCH       WINNEBAGO          IL   TRAINED SPOTTER



0253 PM     TSTM WND GST     LEE                     41.79N 88.94W
08/10/2020  E75 MPH          DE KALB            IL   TRAINED SPOTTER

            ESTIMATED 70 TO 80 MPH WINDS AND DIME SIZE
            HAIL.

0250 PM     TORNADO          2 NNE KIRKLAND          42.11N 88.81W
08/10/2020                   DE KALB            IL   FIRE DEPT/RESCUE

            DRONE FOOTAGE SHOWS A NARROW SWATH OF CORN
            FLATTENED IN A CONVERGENT PATTERN. THIS
            BRIEF EF-0 TORNADO CROSSED BUCK ROAD AND
            PEARL STREET BEFORE LIFTING IN A FIELD EAST
            OF MYELLE ROAD.

0255 PM     TSTM WND DMG     4 SW CALEDONIA          42.33N 88.95W
08/10/2020                   WINNEBAGO          IL   PUBLIC

            TREE DOWN AND DAMAGE TO A METAL STRUCTURE.
            TIME ESTIMATED BY RADAR.

0256 PM     TSTM WND DMG     UTICA                   41.34N 89.01W
08/10/2020                   LA SALLE           IL   TRAINED SPOTTER

            REPORTS OF DAMAGE TO ROOFS AND OUTSIDE
            STRUCTUERS IN UTICA. TIME ESTIMATED BY
            RADAR.

0259 PM     TORNADO          OTTAWA                  41.35N 88.84W
08/10/2020                   LA SALLE           IL   NWS STORM SURVEY

            A BRIEF EF-1 TORNADO WITH PEAK WINDS OF 100
            MPH, PATH LENGTH OF 0.75 MILES, AND MAX
            WIDTH OF 150 YARDS IMPACTED THE NORTH SIDE
            OF OTTAWA DAMAGING ROOFING MATERIAL AND
            SHREDDING TREES ALONG ITS PATH. THE ROOFING
            MATERIAL WAS ORIGINALLY WELL-ANCHORED TO THE
            WALLS, AND A NEARBY SNAPPED POWER POLE
            SUGGESTED A PEAK INTENSITY OF 100 MPH WINDS.
            EYE WITNESS ACCOUNTS CONFIRM THE DAMAGE WAS
            PRODUCED BY A TORNADO BASED ON CLEARLY
            RISING AND SWIRLING MOTION BY MULTIPLE
            SUB-VORTICES IN A BROAD CIRCULATION.

0259 PM     TSTM WND GST     SOMONAUK                41.63N 88.67W
08/10/2020  E90 MPH          DE KALB            IL   PUBLIC

            AN NWS DAMAGE SURVEY FOUND WIDESPREAD TREE
            DAMAGE WITH A FEW TREES SNAPPED VERY NEAR
            THEIR BASE. SEVEN LARGE AND NEW UTILITY
            POLES WERE ALSO SNAPPED ABOUT 10 FEET UP
            FROM THEIR BASE THREE MILES NORTH OF
            SOMONAUK. THE DAMAGE WAS CONSISTENT WITH
            WINDS UP TO AROUND 90 MPH.

0300 PM     TSTM WND DMG     1 E ROCKFORD            42.27N 89.08W
08/10/2020                   WINNEBAGO          IL   FIRE DEPT/RESCUE

            ROCKFORD FIRE CHIEF REPORTS AT LEAST 150
            DAMAGED POWER POLES ACROSS THE CITY.

0300 PM     HAIL             1 WNW BELVIDERE         42.26N 88.86W
08/10/2020  E1.00 INCH       BOONE              IL   TRAINED SPOTTER



0302 PM     TSTM WND DMG     STREATOR                41.12N 88.83W
08/10/2020                   LA SALLE           IL   FIRE DEPT/RESCUE

            SEVERAL TREES SNAPPED AND UPROOTED. TIME
            ESTIMATED BY RADAR.

0305 PM     TORNADO          3 S MARENGO             42.21N 88.60W
08/10/2020                   MCHENRY            IL   NWS STORM SURVEY

            AN EF-1 TORNADO WITH PEAK WINDS OF 95 MPH
            AND PATH LENGTH OF 5.7 MILES TOUCHED DOWN ON
            HARMONY ROAD SOUTHWEST OF I-90 AND CONTINUED
            NORTHEAST BEFORE LIFTING NEAR DUNHAM ROAD
            BETWEEN MARENGO AND UNION. MOST DAMAGE WAS
            CONFINED TO TREES AND TO FARM BUILDINGS
            ALONG THE PATH.

0305 PM     TSTM WND DMG     DEKALB                  41.93N 88.75W
08/10/2020                   DE KALB            IL   TRAINED SPOTTER

            MULTIPLE TREES AND POWER LINES DOWN.
            ESTIMATED 60 MPH GUSTS.

0310 PM     TSTM WND DMG     MAPLE PARK              41.91N 88.60W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            MULTIPLE TREES AND POWER LINES DOWN,
            INCLUDING 10 AND 20 INCH IN DIAMETER TREES.
            FENCES ALSO BLOWN DOWN. TIME ESTIMATED BY
            RADAR.

0312 PM     TORNADO          3 SSW VIRGIL            41.92N 88.55W
08/10/2020                   KANE               IL   PUBLIC

            DRONE FOOTAGE REVEALS A NARROW SWATH OF CORN
            LIKELY AROUND 40 YARDS ACROSS FLATTENED IN A
            CONVERGENT PATTERN. IN ADDITION, DAMAGE TO A
            BARN WAS NOTED, WITH A NEAR COMPLETE REMOVAL
            OF THE ROOF. THIS DAMAGE IS CONSISTENT WITH
            A TORNADO WITH WINDS OF EF-1 INTENSITY.

0314 PM     TSTM WND GST     2 ESE SOMONAUK          41.62N 88.65W
08/10/2020  M57 MPH          LA SALLE           IL   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 57 MPH WIND
            GUST NEAR LAKE HOLIDAY. WIND GUSTS OVER 50
            MPH FOR AT LEAST 15 MINUTES.

0314 PM     TSTM WND GST     3 SSE PLANO             41.63N 88.51W
08/10/2020  M65 MPH          KENDALL            IL   PUBLIC

            PRIVATE WEATHER STATION RECORDED 65 MPH WIND
            GUST.

0315 PM     TSTM WND GST     3 N PONTIAC             40.92N 88.63W
08/10/2020  M54 MPH          LIVINGSTON         IL   AWOS

            PONTIAC AWOS PEAK GUST.

0315 PM     TORNADO          5 W PLAINFIELD          41.60N 88.31W
08/10/2020                   KENDALL            IL   NWS STORM SURVEY

            AN EF-1 TORNADO WITH PEAK WINDS OF 105 MPH,
            PATH LENGTH OF 14.5 MILES, AND MAX WIDTH OF
            250 YARDS STARTED ON THE SOUTH SIDE OF
            YORKVILLE DESTROYING A PERGOLA, TAKING
            SIDING OFF A HOUSE, AND THROWING A TREE
            ACROSS A ROAD. THE TORNADO THEN CONTINUED
            SOUTHEAST AND DAMAGED SEVERAL FARMSTEADS
            INCLUDING THROWING A SHED SEVERAL HUNDRED
            FEET INTO A FIELD AND SCOURING GRASS.
            SEVERAL POWER POLES WERE SNAPPED AT THEIR
            BASE, AS WELL. THE TORNADO CROSSED INTO WILL
            COUNTY SOUTH OF PLAINFIELD AND CONTINUED
            DAMAGING TREES UNTIL ENDING JUST WEST OF
            I-55 NEAR CANTON FARM ROAD. A BROAD AREA OF
            WIND GUSTS OF 70 TO 80 MPH THEN FOLLOWED
            INTO CREST HILL LEADING TO PROLIFIC TREE
            DAMAGE.

0315 PM     TSTM WND DMG     3 E KANEVILLE           41.83N 88.47W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            8 INCH DIAMETER TREE SNAPPED NEAR IL-47 AND
            NOTTINGHAM. RELAYED VIA NWS CHAT, TIME
            ESTIMATED BY RADAR.

0315 PM     TSTM WND DMG     3 ESE MAPLE PARK        41.90N 88.54W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            4 INCH DIAMETER BRANCH DOWNED AND DAMAGE TO
            TRAFFIC SIGNALS AT IL-38 AND MEREDITH ROAD.
            TIME ESTIMATED BY RADAR.

0315 PM     TSTM WND DMG     SOMONAUK                41.63N 88.68W
08/10/2020                   DE KALB            IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS WIDESPREAD TREE AND
            POWER LINE DAMAGE ACROSS SOMANAUK. TREES UP
            TO 4-6 DIAMETER SNAPPED AT THE BASE.

0316 PM     TSTM WND GST     1 WNW SUGAR GROVE       41.77N 88.47W
08/10/2020  M62 MPH          KANE               IL   ASOS

            AURORA ASOS PEAK GUST.

0316 PM     TSTM WND GST     2 W SUGAR GROVE         41.77N 88.48W
08/10/2020  M62 MPH          KANE               IL   ASOS



0317 PM     TSTM WND DMG     DWIGHT                  41.10N 88.43W
08/10/2020                   LIVINGSTON         IL   TRAINED SPOTTER

            NUMEROUS METAL FARM BUILDINGS DAMAGED
            INCLUDING ROOFS AND METAL SIDINGS BLOWN OFF.
            ALSO, LARGE TREE SNAPPED AND DOWNED ONTO A
            HOUSE. TIME ESTIMATED BY RADAR.

0320 PM     TSTM WND DMG     YORKVILLE               41.64N 88.45W
08/10/2020                   KENDALL            IL   TRAINED SPOTTER

            SEVERAL TREES AND LARGE BRANCHES DOWN. TIME
            ESTIMATED BY RADAR.

0320 PM     TSTM WND DMG     2 W SUGAR GROVE         41.76N 88.48W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            TREE DAMAGE BLOCKING FAYS LANE WEST OF SUGAR
            GROVE. TIME ESTIMATED BY RADAR.

0320 PM     TSTM WND DMG     AURORA                  41.76N 88.32W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            10 INCH DIAMETER TREE SNAPPED. TIME
            ESTIMATED BY RADAR.

0323 PM     TSTM WND GST     ROCKFORD AIRPORT        42.20N 89.10W
08/10/2020  M54 MPH          WINNEBAGO          IL   ASOS

            ROCKFORD ASOS PEAK GUST.

0327 PM     HAIL             MORRIS                  41.36N 88.42W
08/10/2020  M1.00 INCH       GRUNDY             IL   TRAINED SPOTTER

            TIME ESTIMATED BY RADAR.

0327 PM     TSTM WND DMG     1 SE WAYNE              41.94N 88.24W
08/10/2020                   DUPAGE             IL   COUNTY OFFICIAL

            TREE DOWN ON ROAD NEAR NANCY LN AND POWIS RD
            IN WAYNE.

0329 PM     TSTM WND DMG     ST. CHARLES             41.91N 88.31W
08/10/2020                   KANE               IL   PUBLIC

            14 INCH DIAMETER TREE SPLIT IN HALF. POWER
            LINES DOWNED. TIME ESTIMATED BY RADAR.

0330 PM     TSTM WND DMG     1 WSW CRYSTAL LAWNS     41.57N 88.18W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            8-IN DIAMETER BRANCHES DOWN NEAR I-55 AND
            CATON FARM ROAD. RELAYED VIA AMATEUR RADIO.
            TIME ESTIMATED BY RADAR.

0330 PM     TSTM WND DMG     RICHMOND                42.48N 88.31W
08/10/2020                   MCHENRY            IL   PUBLIC

            TREE OVER 12 INCHES IN DIAMETER SNAPPED.
            NEAR US-12 AND IL-173.

0330 PM     TSTM WND DMG     FORREST                 40.75N 88.41W
08/10/2020                   LIVINGSTON         IL   PUBLIC

            VIDEO RELAYED VIA SOCIAL MEDIA OF TREE
            DAMAGE IN FORREST.

0330 PM     TSTM WND DMG     4 NW PLAINFIELD         41.65N 88.27W
08/10/2020                   KENDALL            IL   PUBLIC

            DAMAGE TO SIDING OF A HOUSE. SMALL BRANCHES
            DOWNED IN THE VICINITY. TIME ESTIMATED BY
            RADAR.

0330 PM     HAIL             2 NNW MORRIS            41.38N 88.43W
08/10/2020  E1.75 INCH       GRUNDY             IL   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTS GOLFBALL SIZED HAIL
            NEAR I-80 AND LISBON ROAD.

0331 PM     TSTM WND DMG     PLAINFIELD              41.61N 88.21W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            LARGE TREES AND POWER LINES DOWN ACROSS
            PLAINFIELD. TIME ESTIMATED BY RADAR.

0332 PM     TSTM WND GST     2 N PLAINFIELD          41.64N 88.20W
08/10/2020  M84 MPH          WILL               IL   MESONET

            MEASURED BY WEATHERBUG STATION.

0333 PM     TSTM WND DMG     3 NW SHOREWOOD          41.56N 88.23W
08/10/2020                   WILL               IL   PUBLIC

            PUBLIC REPORTS TREES DOWN NEAR CATON FARM
            ROAD AND DRAUDEN ROAD.

0334 PM     TSTM WND DMG     WHEATON                 41.87N 88.11W
08/10/2020                   DUPAGE             IL   TRAINED SPOTTER

            SIX INCH DIAMETER TREE LIMB DOWN. TIME
            ESTIMATED BY RADAR.

0335 PM     TSTM WND GST     5 SE LISBON             41.43N 88.42W
08/10/2020  M59 MPH          GRUNDY             IL   AWOS

            KC09 MORRIS AIRPORT.

0335 PM     TORNADO          1 ENE WHEATON           41.87N 88.10W
08/10/2020                   DUPAGE             IL   NWS STORM SURVEY

            CORRECTS PREVIOUS TORNADO REPORT FROM 1 ENE
            WHEATON. A VERY BRIEF EF-1 TORNADO TOUCHED
            DOWN NEAR THE INTERSECTION OF SEMINARY
            AVENUE AND SCOTT STREET BEFORE MOVING
            NORTHEAST WHERE IT KNOCKED A ROUGHLY 50 FOOT
            STEEPLE AROUND TO THE NORTH SIDE OF THE
            COLLEGE CHURCH IN WHEATON. THE TORNADO THEN
            PRODUCED MINOR TREE DAMAGE BEFORE LIFTING
            NEAR COLLEGE AVENUE AND HOWARD STREET.

0335 PM     TSTM WND DMG     WARRENVILLE             41.82N 88.17W
08/10/2020                   DUPAGE             IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS 1-6 IN DIAMETER TREE
            BRANCHES DOWN ALL OVER WARRENVILLE.

0336 PM     TSTM WND GST     GLEN ELLYN              41.87N 88.06W
08/10/2020  E90 MPH          DUPAGE             IL   NWS STORM SURVEY

            AN NWS DAMAGE SURVEY DETERMINED A CORRIDOR
            OF ENHANCED STRAIGHT LINE WINDS DAMAGED
            TREES AND UTILITY POLES WITH THE MOST
            CONCENTRATED DAMAGE EAST OF NORTH MAIN
            STREET TOWARD LAKE ELLYN PARK. DAMAGE IN THE
            REGION WAS CONSISTENT WITH WIND SPEEDS UP TO
            90 MPH.

0336 PM     TSTM WND DMG     VILLA PARK              41.89N 87.98W
08/10/2020                   DUPAGE             IL   TRAINED SPOTTER

            12 INCH DIAMETER TREE DOWN ON HOUSE. TIME
            ESTIMATED BY RADAR.

0336 PM     TSTM WND DMG     2 W STREAMWOOD          42.02N 88.22W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            ROLLED OVER B-CLASS TRUCK WITH TRAILER AT
            IRVING PARK ROAD AND SCHAUMBURG ROAD.

0338 PM     TSTM WND GST     DUPAGE AIRPORT          41.92N 88.25W
08/10/2020  M62 MPH          DUPAGE             IL   ASOS

            KDPA WEST CHICAGO - DUPAGE ARPT.

0339 PM     TSTM WND DMG     BOLINGBROOK             41.70N 88.07W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            LARGE TREE LIMBS AND SMALL TREES DOWN. TIME
            ESTIMATED BY RADAR.

0339 PM     TORNADO          1 NNE LOMBARD           41.89N 88.00W
08/10/2020                   DUPAGE             IL   NWS STORM SURVEY

            CORRECTS PREVIOUS TORNADO REPORT FROM 1 NNE
            LOMBARD. THE SAME STORM WHICH PRODUCED THE
            BRIEF WHEATON TORNADO PRODUCED ANOTHER
            REGION OF EF-1 TORNADO DAMAGE IMMEDIATELY
            EAST OF I-355 JUST EAST OF LILACIA PARK.
            THIS TORNADO ALSO CONTINUED IN A
            NORTHEASTERLY DIRECTION, UPROOTING
            TREES--SOME SNAPPED AT THE TRUNK--AS WELL AS
            CAUSING SOME HOUSE DAMAGE INCLUDING A FEW
            WITH SUBSTANTIAL ROOF DAMAGE. THE WORST
            DAMAGE OCCURRED NEAR AND AROUND THE LOMBARD
            COMMON JUST SOUTH OF ST. CHARLES ROAD.
            DAMAGE EASED CONSIDERABLY ON THE NORTH SIDE
            OF THE CIRCULATION, WITH A MORE GRADUAL DROP
            OFF IN DAMAGE TO ITS SOUTH. THE TORNADO
            LIFTED JUST NORTHEAST OF THE JEFFERSON
            MIDDLE SCHOOL.

0339 PM     TSTM WND GST     SCHAUMBURG              42.03N 88.08W
08/10/2020  E65 MPH          COOK               IL   TRAINED SPOTTER

            ESTIMATED 60 TO 70 MPH WINDS. TIME ESTIMATED
            BY RADAR.

0340 PM     TSTM WND DMG     1 ENE LAKEMOOR          42.33N 88.18W
08/10/2020                   LAKE               IL   EMERGENCY MNGR

            8-10 INCH DIAMETER LIMBS DOWNED IN THE
            VICINITY OF SULLIVAN LAKE ROAD AND GAME
            TRAIL. SOME BRANCHES WERE UP TO 20 FEET IN
            LENGTH. TIME ESTIMATED BY RADAR.

0340 PM     TSTM WND DMG     CARPENTERSVILLE         42.12N 88.26W
08/10/2020                   KANE               IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS NUMEROUS 6 INCH
            DIAMETER HEALTHY TREE LIMBS DOWN WITH
            SEVERAL WHOLE TREES UPROOTED.

0340 PM     TSTM WND DMG     1 W ROSELLE             41.98N 88.10W
08/10/2020                   DUPAGE             IL   PUBLIC

            PUBLIC REPORTS LARGE LIMBS DOWNED. TIME
            ESTIMATED BY RADAR.

0340 PM     TSTM WND DMG     OAK BROOK               41.83N 87.95W
08/10/2020                   DUPAGE             IL   PUBLIC

            REPORT OF ESTIMATED WINDS UP TO 50MPH, SMALL
            BRANCHES DOWNED, AND HAIL TO HALF INCH
            DIAMETER.

0340 PM     TSTM WND DMG     2 WNW DARIEN            41.76N 88.01W
08/10/2020                   DUPAGE             IL   NWS EMPLOYEE

            CONSIDERABLE TREE DAMAGE ALONG MAIN ST NORTH
            OF 75TH STREET.

0341 PM     TSTM WND GST     2 WNW LOCKPORT          41.60N 88.09W
08/10/2020  M58 MPH          WILL               IL   OFFICIAL NWS OBS

            PEAK WIND GUST MEASURED AT NWS CHICAGO.
            SMALL TREE LIMBS OBSERVED FLYING PAST WINDOW
            AT TIME OF WIND GUST.

0343 PM     TSTM WND DMG     NEW LENOX               41.51N 87.97W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            NUMEROUS LARGE TREES UPROOTED. TIME
            ESTIMATED BY RADAR.

0343 PM     HAIL             1 SSE GLEN ELLYN        41.86N 88.05W
08/10/2020  M1.00 INCH       DUPAGE             IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS QUARTER SIZED HAIL
            NEAR ROOSEVELT ROAD AND IL-53.

0345 PM     FUNNEL CLOUD     1 NNE CREST HILL        41.57N 88.09W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            OBSERVED FROM NEAR CATON FARM ROAD AND
            IL-53.

0345 PM     TSTM WND DMG     3 S NEW LENOX           41.47N 87.96W
08/10/2020                   WILL               IL   PUBLIC

            NUMEROUS TRAFFIC SIGNALS AND A LARGE TREE
            DAMAGED NEAR DELANEY ROAD AND CEDAR ROAD.
            TIME ESTIMATED BY RADAR.

0346 PM     TSTM WND DMG     2 S NEW LENOX           41.48N 87.97W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED HUNDREADS OF TREES
            SNAPPED AND UPROOTED ALONG CEDAR ROAD AND
            JOLIET HIGHWAY.

0348 PM     TSTM WND GST     MOKENA                  41.53N 87.87W
08/10/2020  M65 MPH          WILL               IL   TRAINED SPOTTER

            MEASURED WIND GUST. SMALL TREES DOWNED. TIME
            ESTIMATED BY RADAR.

0349 PM     TSTM WND GST     OHARE AIRPORT           41.98N 87.90W
08/10/2020  M62 MPH          COOK               IL   ASOS

            OHARE ASOS PEAK GUST.

0350 PM     TSTM WND DMG     FRANKFORT               41.50N 87.85W
08/10/2020                   WILL               IL   TRAINED SPOTTER

            SMALL TREES DOWN ACROSS TOWN, ALL IN THE
            SAME DIRECTION. TIME ESTIMATED BY RADAR.

0350 PM     TSTM WND DMG     1 WNW DANFORTH          40.82N 88.00W
08/10/2020                   IROQUOIS           IL   LAW ENFORCEMENT

            OVERTURNED SEMI TRAILER ON I-57 NEAR MILE
            MARKER 287.

0350 PM     HAIL             GLENCOE                 42.13N 87.76W
08/10/2020  M0.88 INCH       COOK               IL   PUBLIC

            NICKEL TO DIME SIZED HAIL REPORTED BY
            TRAINED SPOTTER IN GLENCOE. LASTED 10
            MINUTES FROM 3:50 TO 4:00.

0350 PM     TSTM WND DMG     DUNNING - CHICAGO       41.94N 87.80W
08/10/2020                   COOK               IL   PUBLIC

            GARAGE COLLAPSED. REPORTED AT NORDICA AND
            ROSCOE.

0352 PM     TSTM WND DMG     DUNNING - CHICAGO       41.94N 87.80W
08/10/2020                   COOK               IL   PUBLIC

            SMALL GARAGE PARTIALLY COLLAPSED. TIME
            ESTIMATED BY RADAR.

0353 PM     TSTM WND DMG     KANKAKEE                41.12N 87.86W
08/10/2020                   KANKAKEE           IL   EMERGENCY MNGR

            THE EMERGENCY MANAGER RELAYED REPORTS OF
            TREES UPROOTED ACROSS THE ENTIRE COUNTY.
            TIME ESTIMATED BY RADAR.

0353 PM     TSTM WND DMG     1 SW GILMAN             40.75N 88.01W
08/10/2020                   IROQUOIS           IL   TRAINED SPOTTER

            OVERTURNED SEMI AT MILEPOST 287 ON
            SOUTHBOUND I-57. TIME ESTIMATED BY RADAR.

0354 PM     TORNADO          1 SW MIDLOTHIAN         41.62N 87.73W
08/10/2020                   COOK               IL   NWS STORM SURVEY

            A TORNADO TOUCHED DOWN JUST EAST OF SOUTH
            HARLEM AVENUE IN OAK FOREST, THEN MOVED
            NEARLY DUE EAST ALONG 151ST STREET PRODUCING
            MAINLY MINOR TREE AND STRUCTURAL DAMAGE
            BEFORE LIFTING NEAR THE I-57/I-294
            INTERCHANGE IN MIDLOTHIAN. THE WORST AND
            MOST CONCENTRATED DAMAGE THEN OCCURRED NEAR
            MIDLOTHIAN IN THE REGION BETWEEN CICERO
            AVENUE AND PULASKI ROAD. SEVERAL LARGE TREES
            AND POWER POLES WERE SNAPPED NEAR THEIR
            BASES IN THIS REGION, PRODUCING DAMAGE
            CONSISTENT WITH AN EF-1 TORNADO WITH WINDS
            OF UP TO 100 MPH. DAMAGE FELLED CONSISTENTLY
            IN A CONVERGENT PATTERN TOWARDS THE TRACK
            CENTERLINE. THE TORNADO DAMAGE THEN BEGAN TO
            TRANSITION TO A REGION OF ENHANCED STRAIGHT
            LINE WINDS NEAR THE I-57/294 INTERCHANGE
            WHERE THE DAMAGE BECAME INCREASINGLY
            ORIENTED IN AN EASTERLY DIRECTION. DOWNED
            UTILITY POLES AND SNAPPED TREES INDICATE
            WIND SPEEDS WERE LIKELY NEAR 90 MPH, WITH
            THE MOST NOTABLE DAMAGE CENTERED IN AND
            AROUND THE HARVEY AREA BOUNDED ON THE NORTH
            BY SIBLEY BOULEVARD AND THE SOUTH BY 159TH
            STREET. THIS HIGH DEGREE OF WIND DAMAGE
            PERSISTED EAST INTO THE SHABBONA WOODS
            FOREST PRESERVE BEFORE EASING TOWARDS
            CALUMET CITY.

0355 PM     TSTM WND GST     2 N PAPINEAU            40.99N 87.71W
08/10/2020  M66 MPH          IROQUOIS           IL   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 66 MPH WIND
            GUST.

0355 PM     TSTM WND GST     1 WSW BURBANK           41.74N 87.78W
08/10/2020  M65 MPH          COOK               IL   CO-OP OBSERVER

            ALSO HAD PEA SIZE HAIL.

0357 PM     TSTM WND DMG     1 SW ALBANY PARK - CHIC 41.96N 87.73W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            BRICKS KNOCKED OFF TOP OF BUILDING AND TREES
            DOWNED. TIME ESTIMATED BY RADAR.

0357 PM     TSTM WND DMG     OAK FOREST              41.60N 87.74W
08/10/2020                   COOK               IL   PUBLIC

            50 TO 60 FOOT TALL TREES DOWNED. TIME
            ESTIMATED BY RADAR.

0357 PM     TORNADO          PARK FOREST             41.48N 87.69W
08/10/2020                   COOK               IL   NWS STORM SURVEY

            NWS STORM SURVEY DETERMINED THAT A BRIEF
            TORNADO TOUCHED DOWN VERY CLOSE TO THE
            COOK/WILL COUNTY LINE NEAR SHABBONA DRIVE.
            IT TRACKED NORTHEAST WHERE IT PRODUCED A
            LOCALIZED AREA OF FAIRLY WIDESPREAD TREE
            DAMAGE CONSISTENT WITH HIGH-END EF-0 WIND
            SPEEDS. THE WORST DAMAGE WAS CONFINED TO A
            SMALL AREA NEAR MARQUETTE AND SOMONAUK
            PARKS, ALTHOUGH VERY LITTLE STRUCTURAL
            DAMAGE WAS NOTED. THE TORNADO LIFTED OVER
            SCHUBERTS WOODS FOREST PRESERVE. SPORADIC
            STRAIGHT-LINE WIND DAMAGE OCCURRED EAST
            TOWARDS STATE STREET.

0357 PM     TSTM WND DMG     1 SSE LINCOLN SQUARE -  41.97N 87.68W
08/10/2020                   COOK               IL   PUBLIC

            REPORTED AT 2105 W EASTWOOD DR, CHICAGO, IL.
            LARGE TREE DOWN AND LARGE BRANCHES BROKEN
            OUT OF OTHER TREES.

0357 PM     TSTM WND GST     LINCOLN SQUARE - CHICAG 41.98N 87.69W
08/10/2020  M85 MPH          COOK               IL   MESONET

            MEASURED BY WEATHERBUG STATION.

0357 PM     TSTM WND GST     1 NE MIDWAY AIRPORT     41.79N 87.74W
08/10/2020  M72 MPH          COOK               IL   ASOS

            MIDWAY ASOS PEAK GUST.

0357 PM     TSTM WND DMG     1 S MONTROSE HARBOR     41.95N 87.64W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            REPORTS OF A ROOF BLOWN OFF A BUILDING NORTH
            OF ADDISON AND LAKE SHORE DRIVE.

0359 PM     TORNADO          1 N WEST RIDGE - CHICAG 42.01N 87.70W
08/10/2020                   COOK               IL   NWS STORM SURVEY

            AN NWS DAMAGE SURVEY CONFIRMED AN EF-1
            TORNADO WITH ESTIMATED PEAK WINDS OF 110
            MPH, PATH LENGTH OF 3 MILES, AND MAX WIDTH
            OF 300 YARDS TOUCHED DOWN NEAR CRAWFORD AVE
            IN THE LINCOLNWOOD NEIGHBROHOOD OF CHICAGO
            AND PROGRESSED EAST NORTHEASTWARD THROUGH
            PHILLIP ROGERS PARK. THE TORNADO THEN MOVED
            THROUGH POTTAWATTOMIE PARK AND ROUGHLY ALONG
            W FARGO AVE BEFORE CROSSING ONTO LAKE
            MICHIGAN. THERE WERE NO CONFIRMED INJURIES
            OR FATALITIES.

0359 PM     TSTM WND DMG     OAK LAWN                41.72N 87.75W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            LARGE TREE UPROOTED IN OAK LAWN. TIME
            ESTIMATED BY RADAR.

0400 PM     TSTM WND DMG     STEGER                  41.47N 87.64W
08/10/2020                   WILL               IL   EMERGENCY MNGR

            WIDESPREAD WIND DAMAGE THROUGHOUT STEGER
            INCLUDING TREES DOWN, TREES ON POWER LINES,
            AND POWER POLES BROKEN.

0400 PM     TSTM WND DMG     4 ESE SAMMONS POINT     41.01N 87.79W
08/10/2020                   KANKAKEE           IL   PUBLIC

            TREE DAMAGE NEAR 7500S ROAD WEST OF ST ANNE.
            TIME ESTIMATED BY RADAR.

0400 PM     TSTM WND DMG     CRESCENT CITY           40.77N 87.86W
08/10/2020                   IROQUOIS           IL   TRAINED SPOTTER

            LARGE TREES AND POWER POLES DOWN ACROSS
            ENTIRE COUNTY. ALSO REPORTED BILLBOARD
            DAMAGE. TIME ESTIMATED BY RADAR.

0400 PM     TSTM WND GST     4 SW CHANNAHON          41.40N 88.28W
08/10/2020  M57 MPH          GRUNDY             IL   MESONET

            USACE STATION AT DRESDEN LOCK AND DAM
            OBSERVED 57 MPH GUST.

0400 PM     TSTM WND DMG     1 W NAVY PIER           41.89N 87.62W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            NUMEROUS REPORTS OF DOWNED TREE LIMBS ACROSS
            WRIGLEYVILLE, ROSCOE VILLAGE, LOGAN SQUARE,
            AND LINCOLN SQUARE. TIME ESTIMATED BY RADAR.

0400 PM     TSTM WND DMG     2 NNE BRIDGEPORT - CHIC 41.86N 87.64W
08/10/2020                   COOK               IL   LAW ENFORCEMENT

            POSSIBLE STRUCTURE DAMAGE NEAR 18TH AND
            CANALPORT AVENUE IN CHICAGO.

0400 PM     TSTM WND DMG     1 NW HARVEY             41.62N 87.66W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            EXTENSIVE DAMAGE TO TREES REPORTED IN THE
            AREA ALONG 149TH AND 150TH IN HARVEY,
            ESPECIALLY EAST OF DIXIE HWY. POSSIBLE
            TORNADO.

0400 PM     TSTM WND GST     1 ENE HARVEY            41.61N 87.64W
08/10/2020  E90 MPH          COOK               IL   NWS STORM SURVEY

            AN NWS STORM SURVEY DETERMINED A REGION OF
            ENHANCED STRAIGHT LINE WINDS OCCURRED IN AND
            AROUND THE HARVEY AREA. DOWNED UTILITY POLES
            AND SNAPPED TREES INDICATE WIND SPEEDS WERE
            LIKELY NEAR 90 MPH. THE WORST DAMAGE WAS
            BOUNDED ON THE NORTH BY SIBLEY BOULEVARD AND
            THE SOUTH BY 159TH STREET. THIS HIGH DEGREE
            OF WIND DAMAGE PERSISTED EAST INTO THE
            SHABBONA WOODS FOREST PRESERVE BEFORE EASING
            TOWARDS CALUMET CITY.

0402 PM     MARINE TSTM WIND 1 NE MONTROSE HARBOR    41.97N 87.63W
08/10/2020  M80 MPH          LMZ741             IL   MESONET

            MESONET STATION XMTB MONTROSE BEACH.

0402 PM     MARINE TSTM WIND 3 NE NAVY PIER          41.92N 87.57W
08/10/2020  M72 MPH          LMZ741             IL   C-MAN STATION

            HARRISON DEVER CRIB MEASURED A 63 KT WIND
            GUST.

0402 PM     TSTM WND DMG     CHICAGO HEIGHTS         41.51N 87.64W
08/10/2020                   COOK               IL   PUBLIC

            45 FOOT PINE TREE DOWNED. TIME ESTIMATED BY
            RADAR.

0403 PM     TSTM WND DMG     EVANSTON                42.04N 87.69W
08/10/2020                   COOK               IL   TRAINED SPOTTER

            NUMEROUS TREES SNAPPED AND UPROOTED IN
            EVANSTON. TIME ESTIMATED BY RADAR.

0403 PM     TSTM WND DMG     LAKEVIEW - CHICAGO      41.94N 87.66W
08/10/2020                   COOK               IL   PUBLIC

            LARGE TREE SNAPPED. TIME ESTIMATED BY RADAR.

0404 PM     WATER SPOUT      1 NE ROGERS PARK - CHIC 42.02N 87.66W
08/10/2020                   LMZ741             IL   PUBLIC

            YOUTUBE VIDEO SHOWS FOOTAGE OF A TORNADO IN
            ROGERS PARK MOVING OUT OVER LAKE MICHIGAN AS
            A WATERSPOUT.

0404 PM     TORNADO          GRANT PARK              41.24N 87.65W
08/10/2020                   KANKAKEE           IL   NWS STORM SURVEY

            AN EF-0 TORNADO WITH PATH LENGTH OF 1.5
            MILES, MAX WIDTH 250 YARDS, AND PEAK WINDS
            OF 80 MPH STARTED JUST NORTHWEST OF GRANT
            PARK ON N 11000 E ROAD, TRAVELED SOUTHEAST
            THROUGH GRANT PARK, AND ENDED NEAR LAKE
            METONGA. DAMAGE WAS MAINLY TO TREES ALONG
            THE DAMAGE PATH.

0405 PM     TSTM WND DMG     GRANT PARK              41.24N 87.64W
08/10/2020                   KANKAKEE           IL   TRAINED SPOTTER

            LARGE TREES DOWNED. TIME ESTIMATED BY RADAR.

0405 PM     TSTM WND GST     1 NE PARK FOREST        41.49N 87.68W
08/10/2020  M70 MPH          COOK               IL   AMATEUR RADIO

            MEASURED WIND GUST OF 72 MPH NEAR FIR STREET
            RELAYED VIA AMATEUR RADIO.

0408 PM     TSTM WND DMG     ST. JOHN                41.45N 87.47W
08/10/2020                   LAKE               IN   PUBLIC

            SEVERAL TREES SNAPPED.

0408 PM     TSTM WND GST     1 SE THORNTON           41.57N 87.61W
08/10/2020  E60 MPH          COOK               IL   TRAINED SPOTTER

            TRAINED SPOTTER ESTIMATES WINDS OF 60 MPH IN
            THORNTON. RELAYED VIA AMATEUR RADIO.

0408 PM     TSTM WND GST     WEST RIDGE - CHICAGO    42.00N 87.69W
08/10/2020  M57 MPH          COOK               IL   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 57MPH GUST
            IN WEST RIDGE NEIGHBORHOOD OF CHICAGO.

0409 PM     TSTM WND DMG     1 NW CICERO             41.86N 87.77W
08/10/2020                   COOK               IL   PUBLIC

            PUBLIC REPORT OF TREE DAMAGE IN CICERO.

0410 PM     TSTM WND DMG     1 NW LOGAN SQUARE - CHI 41.93N 87.71W
08/10/2020                   COOK               IL   LAW ENFORCEMENT

            TREE BLOCKING KEZIE BLVD AT LOGAN BLVD IN
            LOGAN SQUARE NEIGHBORHOOD OF CHICAGO.

0415 PM     TORNADO          4 WSW BROOK             40.85N 87.43W
08/10/2020                   NEWTON             IN   EMERGENCY MNGR

            THIS EF-0 TORNADO WAS ON THE GROUND FOR LESS
            THAN 1 MINUTE AND PRODUCED MINOR DAMAGE TO A
            METAL FARM BUILDING IMMEDIATELY WEST OF
            STATE HIGHWAY 41.

0415 PM     TSTM WND GST     1 SW HAMMOND            41.57N 87.51W
08/10/2020  M61 MPH          LAKE               IN   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 61 MPH
            GUST.

0415 PM     TSTM WND DMG     1 WSW CEDAR LAKE        41.36N 87.45W
08/10/2020                   LAKE               IN   PUBLIC

            6 INCH DIAMETER TREE DOWNED NEAR PARRISH
            AVENUE AND 141ST AVENUE IN CEDAR LAKE. TIME
            ESTIMATED BY RADAR.

0416 PM     TSTM WND GST     GARY AIRPORT            41.62N 87.41W
08/10/2020  M55 MPH          LAKE               IN   AWOS

            GARY AWOS PEAK GUST.

0416 PM     TSTM WND DMG     CROWN POINT             41.42N 87.36W
08/10/2020                   LAKE               IN   PUBLIC

            LARGE TREE SNAPPED. TIME ESTIMATED BY RADAR.

0418 PM     TSTM WND GST     1 ESE NAPERVILLE        41.77N 88.14W
08/10/2020  E60 MPH          DUPAGE             IL   BROADCAST MEDIA



0420 PM     TSTM WND DMG     4 W BROOK               40.87N 87.43W
08/10/2020                   NEWTON             IN   LAW ENFORCEMENT

            POWERLINES DOWN ACROSS US-41 NEAR IN-16
            BETWEEN MOROCCO AND KENTLAND. TIME ESTIMATED
            BY RADAR.

0421 PM     TSTM WND DMG     4 N KENTLAND            40.83N 87.43W
08/10/2020                   NEWTON             IN   EMERGENCY MNGR

            30 BY 50 FOOT CORN FIELD FLATTENED WITH
            SWILING DENOTED IN CORNFALL. ALSO, METAL
            SHEDS DAMAGED WITH PARTS OF ROOFS AND DOORS
            MISSING. NO MAJOR STRUCTURE DAMAGE WAS NOTED
            TO FARM HOUSES IN THE AREA. POSSIBLE
            TORNADO. TIME ESTIMATED BY RADAR.

0421 PM     TSTM WND DMG     MOROCCO                 40.95N 87.45W
08/10/2020                   NEWTON             IN   PUBLIC

            BRICK CHIMNEY BLOWN DOWN; MULTIPLE TREE
            LIMBS BLOWN DOWN. TIME ESTIMATED BY RADAR.

0425 PM     TSTM WND GST     5 WNW KENTLAND          40.80N 87.53W
08/10/2020  M73 MPH          NEWTON             IN   PUBLIC

            PRIVATE WEATHER STATION OBSERVED 73 MPH GUST
            WEST OF KENTLAND. TIME ESTIMATED BY RADAR.

0425 PM     NON-TSTM WND GST 1 W ELMHURST            41.90N 87.95W
08/10/2020  M57 MPH          DUPAGE             IL   MESONET

            PRIVATE WEATHER STATION OBSERVED 57 MPH
            GUST.

0429 PM     TSTM WND GST     1 NNW WINFIELD          41.42N 87.28W
08/10/2020  M60 MPH          LAKE               IN   PUBLIC

            PRIVATE WEATHER STATION RECORDED 60 MPH
            GUST.

0431 PM     TSTM WND DMG     3 ESE WHEELER           41.50N 87.12W
08/10/2020                   PORTER             IN   TRAINED SPOTTER

            DOWNED TREES AND TRAMPOLINE THROWN ACROSS
            YARD.

0432 PM     TSTM WND DMG     3 SW VALPARAISO         41.45N 87.10W
08/10/2020                   PORTER             IN   TRAINED SPOTTER

            FOUR 8 TO 10 INCH IN DIAMETER SNAPPED.

0439 PM     TSTM WND GST     KOUTS                   41.32N 87.03W
08/10/2020  E70 MPH          PORTER             IN   TRAINED SPOTTER

            ESTIMATED 70 MPH WIND GUSTS. TIME ESTIMATED
            BY RADAR.

0440 PM     TSTM WND DMG     PORTAGE                 41.58N 87.18W
08/10/2020                   PORTER             IN   EMERGENCY MNGR

            DAMAGE TO THE ROOF OF A STRIP MALL ALONG
            CENTRAL AVENUE IN PORTAGE. TIME ESTIMATED BY
            RADAR.

0440 PM     TSTM WND DMG     1 S PORTAGE             41.56N 87.18W
08/10/2020                   PORTER             IN   TRAINED SPOTTER

            TRAINED SPOTTER REPORTS 10 INCH DIAMETER
            BRANCH DOWNED ON LUTE ROAD IN PORTAGE. TIME
            ESTIMATED BY RADAR.

0441 PM     TSTM WND DMG     1 S VALPARAISO          41.46N 87.06W
08/10/2020                   PORTER             IN   TRAINED SPOTTER

            SEMI BLOWN OVER NEAR VALPARAISO. TIME
            ESTIMATED BY RADAR.

0456 PM     MARINE TSTM WIND 3 NE NAVY PIER          41.92N 87.57W
08/10/2020  M55 MPH          LMZ741             IL   C-MAN STATION

            **DELAYED REPORT** RECORDED AT THE
            HARRISON-DEVER CRIB. GUSTS ABOVE 35 MPH
            CONTINUED UNTIL 5:18 PM CDT.

Tornadoes:

As of Saturday, August 15, there have been 15 tornadoes confirmed across northern Illinois and northwest Indiana. 

Full Public Information Statement on the tornadoes

Downloadable KMZ file featuring all tornado paths and wind swaths/damage

Downloadable shapefile featuring all tornado paths and wind swaths/damage

Tornadoes are listed in chronological order:

Tornado #7 - Yorkville to South Plainfield EF-1 KENDALL/WILL COUNTY

Zoomed-in Maps

Downloadable KMZ file Downloadable shapefile Summary:  The tornado started on the far south side of Yorkville near Walsh Drive where a pergola was destroyed, siding was ripped off a house, and parts of a fence and a tree were thrown over a roadway. Eyewitnesses accounts indicate the debris was lifted and twirled, consistent with a tornado. The tornado then progressed east-southeastward producing damage to trees along State Route 126 toward Schlapp Road. The most significant damage was found east of Schlapp Road along Wheeler road where trees were mangled, a farm building was destroyed with debris deposited in a nearby field, and a large grain bin was bent inward. Wood panels were thrown into the ground leaving scour marks in the grass. Six power poles were snapped along Ridge Road, and a 1000-1500 lb auger was moved about 50 feet. This is where the tornado likely reached peak intensity with winds near 105 mph. The tornado continued southeast into neighborhoods south of Renwick Road producing mainly tree damage, and ended just before I-55. A swath of damaging winds consistent with speeds of 70 to 80 mph continued into Crest Hill based on prolific tree damage.

The Enhanced Fujita (EF) Scale classifies tornadoes into the following categories:

EF0 Weak 65-85 mph	EF1 Moderate 86-110 mph	EF2 Significant 111-135 mph	EF3 Severe 136-165 mph	EF4 Extreme 166-200 mph	EF5 Catastrophic 200+ mph

Radar:

Loops

Composite radar (highest intensity within the column) of derecho across northern Illinois courtesy of NWS Milwaukee.	Lowest level radar scans of derecho across northern Illinois.

Summary of the radar presentation during severe wind damage in Harvey, IL in southern Cook County.

Photos:

Approaching Derecho

Shelf cloud 2 miles west of Mendota, IL courtesy of Heather Friedlein	Shelf cloud near Lisle, IL courtesy of Keith Langosch	Shelf cloud from near Sugar Grove, IL courtesy of Maddie Murphy.

Tornadoes

Ottawa, IL tornado courtesy of Jason Ward.

Storm Damage

Kendall County to Will County tornado - NWS Survey	Kendall County to Will County tornado - NWS Survey	Kendall County to Will County tornado - NWS Survey	Kendall County to Will County tornado - NWS Survey

Elburn, IL, courtesy of Matt Taylor	Midlothian, IL, courtesy of Matt Kooi

Ottawa, IL courtesy of Matthew Spika	Ottawa, IL courtesy of Gilbert Sebenste	Wheaton, IL church steeple damage courtesy of Carrie Vicek-Jodelka

Somonauk, IL courtesy of Bob Waszak	Chicago, Albany Park neighborhood, courtesy of Alex Forgue	Chicago, Rogers Park neighborhood, courtesy of Paul Navarro	Chicago, Dunning neighborhood area, courtesy of Twitter follower @Jasong1451

New Lenox, IL courtesy of the Joliet Weather Center	New Lenox, IL courtesy of Dan Casper	Dwight, IL courtesy of Andrew Pritchard

Environment

Aug 10, 9 a.m. 500 mb (~18,000 ft) level, showing a strong short wave and associated 50-70 kt speed maximum moving eastward across the Upper Midwest. This would be a drive force for continued upper support through the thunderstorm complex's lifecycle.

Aug 10, 9 a.m. surface weather map highlighting the very moist air mass ahead of the maturing thunderstorm complex at that time. Note the warm front also slowly moving north. This boundary supported continued low-level warm and moist advection (fuel to the storms), as well as a source for low-level veering profiles near it increasing tornadogenesis potential especially in the toward the IL/WI state line by mid afternoon.

NWS Quad Cities weather balloon launch at 12 p.m. on August 10 that sampled a high amount of instability thanks to exceptionally steep mid-level lapse rates and very high equilibrium levels, ample moisture, and undirectional mid-level flow of sufficient amount for long-lived, organized, forward-propagating storms.

Aug 10, 11 a.m. deep layer wind shear, with values of 40+ kt sufficient for storm organization, and given the unidirectional mid-level wind profile, this also would help support the development of a forward-propagating storm complex.	Aug 10, 11 a.m. surface-based CAPE (instability), with widespread values over 2,500 J/kg indicating a strongly unstable air mass ahead of the incoming thunderstorm complex.	Aug 10, 11 a.m. precipitable water, with an ample moisture reservoir present for the replenishing of moisture into the thunderstorm complex.

Aug 10, 11 a.m. mid-level lapse rates with 8C/km or higher through that layer reflecting the potential for rapidly accelerating updrafts. Combined with sufficient low-level moisture and heating, this indicates explosive convection processes.	Aug 10, 11 a.m. low-level wind shear with values of 20-25 kt (that likely increased further as the complex strengthened) indicating cold pool organization from rain-cooled air. A cold pool allows for stronger storm forward motion and wind momentum given the other ingredients. Also these values are sufficient enough for tornado potential if defined storm inflow areas that can harness low-level turning were to develop.	Aug 10, 11 a.m. MCS maintenance parameter, which provides probabilistic information combining shear profile data, mid-level lapse rates, instability, and mid and upper level wind flow. High probabilities of 90+ percent for ~200 miles ahead of the maturing storm complex are not surprising given the high values of these input parameters.

NWS Des Moines Doppler Radar Vertical Wind Profile data (separate tab for full resolution)	NWS Quad Cities Doppler Radar Vertical Wind Profile data (separate tab for full resolution)	NWS Chicago/Romeoville Doppler Radar Vertical Wind Profile data (separate tab for full resolution)
These are basically cross-sections of the derecho's wind profile, namely its rear-inflow jet (RIJ), as the system moved from west-to-east over the area. The RIJ is most mature as the system moves over the Quad Cities, with impressive 100+ mph winds immediately off the surface (some realized at the surface). Notice the unidirectional northwest flow of the low-level jet, ideal for momentum transfer of the strongest winds to the surface that was realized with frequent severe wind gusts persisting a half hour in places! Also interesting to note is the wind profile immediately ahead of the front edge of the derecho's front edge (i.e. the wind shift). For the NWS Chicago profile data, there is more low-level shear (~0-1.5 km) in that immediate pre-storm environment which may explain the tendency for more mesovortices and in turn corridors of enhanced wind damage and tornadoes in our area vs. further west.

Click image for 14-hour satellite loop of the derecho shared on Twitter.

Rain Reports

Public Information Statement
National Weather Service Chicago IL
1103 PM CDT Tue Aug 11 2020 /1203 AM EDT Wed Aug 12 2020/

...Rainfall from Monday August 10th...

The following are rainfall amounts as measured in the morning by
NWS Cooperative observers and CoCoRaHS observers. Observations are
usually taken at 7 AM.

ILLINOIS                                     Rainfall
  Location (County):                         Amt(inches)

  South Beloit 2SE (Winnebago).................2.66
  Roscoe 2se (Winnebago).......................2.48
  Roscoe 2ESE (Winnebago)......................2.48
  Capron (Boone)...............................2.46
  Rockford 2ENE (Winnebago)....................1.30
  Hebron (McHenry).............................1.22
  Lake Villa 1SSW (Lake).......................1.00
  Woodstock 5nw (McHenry)......................0.98
  Brandon Road Lock & Dam (Will)...............0.94
  Lake Villa 2WSW (Lake).......................0.92
  Gurnee 2W (Lake).............................0.91
  Woodstock 4SW (McHenry)......................0.87
  Oregon (Ogle)................................0.85
  Bull Valley 2WNW (McHenry)...................0.83
  Kingston 2WNW (De Kalb)......................0.82
  New Lenox 3ENE (Will)........................0.75
  Morris 6ESE (Grundy).........................0.75
  McHenry (Stratton Lock & Dam) (McHenry)......0.74
  Winthrop Harbor (Lake).......................0.74
  New Lenox 3E (Will)..........................0.73
  Mokena 1W (Will).............................0.73
  Woodstock 1SSW (McHenry).....................0.73
  Lakemoor 2NW (McHenry).......................0.73
  Channahon 2SSE (Will)........................0.72
  Winthrop Harbor 1SSW (Lake)..................0.72
  Midlothian (Cook)............................0.72
  Carbon Hill 3.1N (Grundy)....................0.71
  Genoa (De Kalb)..............................0.71
  Coal City 4NNW (Grundy)......................0.71
  Beecher 3ENE (Will)..........................0.70
  Glen Ellyn 2SSE (Du Page)....................0.70
  Bourbonnais (Kankakee).......................0.70
  Plainfield 2SSE (Will).......................0.69
  Lake Forest 2NNE (Lake)......................0.69
  Manhattan 2SE (Will).........................0.68
  Round Lake 2WNW (Lake).......................0.68
  Elwood 5NE (Will)............................0.67
  Lockport 1SE (Will)..........................0.66
  Plainfield 3ESE (Will).......................0.66
  Aurora 4SE (Du Page).........................0.66
  Oak Park 2S (Cook)...........................0.66
  Elmhurst 1ESE (Du Page)......................0.64
  Wilmington 6NW (Will)........................0.63
  Naperville 4SSW (Will).......................0.63
  Wilmington 3SE (Will)........................0.63
  Morris 2SSE (Grundy).........................0.63
  Aurora 4SE (Du Page).........................0.63
  La Grange Park 1SSW (Cook)...................0.63
  Crystal Lake 1WSW (McHenry)..................0.62
  La Salle (La Salle)..........................0.62
  Naperville 2SE (Du Page).....................0.62
  Oak Park 1SW (Cook)..........................0.62
  Oak Lawn 2SE (Cook)..........................0.62
  DeKalb (De Kalb).............................0.62
  Joliet 2n (Will).............................0.61
  Crete 3E (Will)..............................0.61
  Plano (Kendall)..............................0.61
  Huntley (McHenry)............................0.59
  Naperville 2ESE (Du Page)....................0.59
  Peru 1ENE (La Salle).........................0.58
  De Kalb 1SW (De Kalb)........................0.58
  Oswego 5SSE (Kendall)........................0.57
  Waukegan (Lake)..............................0.56
  Steward (Lee)................................0.56
  Pontiac (Livingston).........................0.56
  Algonquin 1N (McHenry).......................0.56
  Beecher 3SSE (Will)..........................0.55
  Westmont 1SSW (Du Page)......................0.55
  Oak Forest 1SSE (Cook).......................0.55
  Joliet 3WNW (Will)...........................0.54
  Cary (McHenry)...............................0.54
  Emington 2SSE (Livingston)...................0.54
  Somonauk 2NE (De Kalb).......................0.54
  Naperville 2ESE (Du Page)....................0.53
  Seneca 1NNE (La Salle).......................0.52
  Gilberts (Kane)..............................0.52
  Cortland (De Kalb)...........................0.52
  Glen Ellyn (Du Page).........................0.52
  Lisle Morton Arb (Du Page)...................0.51
  Rockford (Winnebago).........................0.51
  Peru 1SW (La Salle)..........................0.51
  Gibson 3WNW (Ford)...........................0.51
  Elmhurst 2SE (Du Page).......................0.51
  Oak Lawn (Cook)..............................0.51
  Morris (Grundy)..............................0.50
  Elgin (Kane).................................0.50
  Park Forest 1NNE (Cook)......................0.49
  Rogers Park 2SW (Cook).......................0.49
  Chicago Ridge (Cook).........................0.49
  Waukegan 2N (Lake)...........................0.48
  Dixon 3NNW (Lee).............................0.48
  Elgin 2W (Kane)..............................0.48
  Coal City 3N (Grundy)........................0.48
  Homewood (Cook)..............................0.48
  Park Forest (Cook)...........................0.47
  Paw Paw (Lee)................................0.47
  Watseka 6.9WNW (Iroquois)....................0.47
  Morris 5NNW (Grundy).........................0.47
  Naperville 1NW (Du Page).....................0.47
  Westmont (Du Page)...........................0.46
  Mundelein (Lake).............................0.46
  Elgin 2WNW (Kane)............................0.46
  Glencoe (Cook)...............................0.46
  Winnetka 1ESE (Cook).........................0.46
  Aurora (Kane)................................0.46
  Romeoville (Will)............................0.45
  Lake Zurich 1N (Lake)........................0.45
  Riverwoods (Lake)............................0.44
  Ashton (Lee).................................0.44
  Sugar Grove 1NE (Kane).......................0.44
  Buckley (Iroquois)...........................0.44
  Ashkum 5.6E (Iroquois).......................0.44
  Bolingbrook 3NE (Du Page)....................0.44
  Peotone (Will)...............................0.43
  Channahon 1NNE (Will)........................0.43
  Peotone (Will)...............................0.43
  Sugar Grove 1ENE (Kane)......................0.43
  Morris (Grundy)..............................0.43
  Lansing (Cook)...............................0.42
  Mendota (La Salle)...........................0.42
  Geneva 1SSW (Kane)...........................0.42
  Lincolnwood 2E (Cook)........................0.42
  O`hare Airport (Cook)........................0.41
  Mendota (La Salle)...........................0.41
  Mundelein (Lake).............................0.41
  Batavia 1WNW (Kane)..........................0.41
  Batavia 1WSW (Kane)..........................0.40
  Minooka (Grundy).............................0.40
  Elk Grove Village 2WSW (Cook)................0.40
  Lemont (Cook)................................0.40
  Chatsworth (Livingston)......................0.40
  Bannockburn (Lake)...........................0.39
  North Aurora 2NE (Kane)......................0.39
  Geneva 4WSW (Kane)...........................0.39
  Montgomery 1SSE (Kendall)....................0.39
  Lisle (Du Page)..............................0.39
  Highwood 1S (Lake)...........................0.38
  Batavia 2WNW (Kane)..........................0.38
  Lisle 1SE (Du Page)..........................0.38
  Oak Park 1NNE (Cook).........................0.38
  Oak Lawn 1N (Cook)...........................0.38
  Roselle 1ESE (Du Page).......................0.37
  Dwight (Livingston)..........................0.37
  Homer Glen 1ENE (Will).......................0.36
  Pontiac 1SE (Livingston).....................0.36
  North Utica 6N (La Salle)....................0.36
  Libertyville 2ESE (Lake).....................0.36
  Darien (Du Page).............................0.36
  Earlville 5NNE (De Kalb).....................0.36
  Mount Prospect 3NE (Cook)....................0.36
  Batavia (Kane)...............................0.36
  Paxton (Ford)................................0.35
  Ottawa 2N (La Salle).........................0.35
  Lake Bluff 1W (Lake).........................0.35
  St. Charles 6NW (Kane).......................0.35
  St. Charles (Kane)...........................0.35
  Midway Coop (Cook)...........................0.34
  Lisle 1SW (Du Page)..........................0.34
  Palatine 1NNE (Cook).........................0.34
  Lake Zurich (Lake)...........................0.33
  Buffalo Grove 2N (Lake)......................0.33
  Herscher 3E (Kankakee).......................0.33
  Plainfield 5SW (Kendall).....................0.33
  Earlville 3S (La Salle)......................0.33
  Schaumburg (Du Page).........................0.33
  Wheeling (Cook)..............................0.32
  Midway (Cook)................................0.32
  Coal City (Grundy)...........................0.32
  Gibson 6NE (Ford)............................0.32
  Burr Ridge 2SW (Du Page).....................0.32
  Bartlett 1SE (Du Page).......................0.32
  Wheaton 2NNE (Du Page).......................0.31
  Elk Grove Village 1ESE (Cook)................0.31
  Elmwood Park 1ESE (Cook).....................0.31
  West Chicago (Du Page).......................0.31
  Ottawa (La Salle)............................0.30
  Lombard 1NNW (Du Page).......................0.30
  Elmhurst (Du Page)...........................0.30
  Marseilles 5WNW (La Salle)...................0.29
  Arlington Heights 1S (Cook)..................0.28
  Hoffman Estates 5W (Cook)....................0.28
  Lincolnshire 1N (Lake).......................0.27
  Harwood Heights (Cook).......................0.27
  Ottawa 1NW (La Salle)........................0.25
  Palos Park 1SW (Cook)........................0.25
  St Anne (Kankakee)...........................0.24
  Paxton (Ford)................................0.24
  Bridgeview 1NNW (Cook).......................0.24
  Ottawa (La Salle)............................0.23
  Schaumburg 2E (Cook).........................0.23
  Cissna Park 1S (Iroquois)....................0.22
  Park Ridge (Cook)............................0.22
  Cropsey 1NE (Livingston).....................0.21
  Hoffman Estates 2SE (Cook)...................0.21
  Park Ridge 1WNW (Cook).......................0.20
  Streator (Livingston)........................0.18

INDIANA                                      Rainfall
  Location (County):                         Amt(inches)

  Hebron 1NW (Porter)..........................1.34
  Hebron 3SW (Lake)............................1.24
  Remington (Jasper)...........................1.15
  Lakes Of The Four Seasons (Porter)...........0.94
  Wheatfield 5W (Jasper).......................0.94
  Wheatfield 3S (Jasper).......................0.88
  Rensselaer 5NW (Jasper)......................0.84
  Mount Ayr 2NNE (Newton)......................0.80
  Hebron 4NE (Porter)..........................0.74
  Rensselaer (Jasper)..........................0.70
  Rensselaer 2N (Jasper).......................0.69
  De Motte 1NNW (Jasper).......................0.69
  Rensselaer 2SSW (Jasper).....................0.69
  Crown Point (Lake)...........................0.68
  Crown Point 1N (Lake)........................0.67
  Rensselaer 4N (Jasper).......................0.64
  De Motte 1SW (Jasper)........................0.64
  De Motte 6S (Jasper).........................0.64
  De Motte 1SSW (Jasper).......................0.62
  Rensselaer 10NNE (Jasper)....................0.61
  Wheatfield 4WSW (Jasper).....................0.59
  Rensselaer 8ENE (Jasper).....................0.59
  Porter 1S (Porter)...........................0.54
  Valparaiso 4SW (Porter)......................0.50
  Valparaiso 2N (Porter).......................0.49
  Portage 3E (Porter)..........................0.48
  Hammond 1SSW (Lake)..........................0.46
  Valparaiso 2NW (Porter)......................0.43
  Chesterton 1ENE (Porter).....................0.42
  Kentland 2SSE (Newton).......................0.42
  Rensselaer 6SE (Jasper)......................0.41
  Indiana Dunes (Porter).......................0.41
  Schererville 2ESE (Lake).....................0.38
  Hobart 2E (Lake).............................0.37
  Hobart 1SSW (Lake)...........................0.36
  Kentland (Newton)............................0.35
  Chesterton 4E (Porter).......................0.34
  Gary 5ENE (Lake).............................0.33
  Valparaiso 6SSW (Porter).....................0.30
  Schererville 1E (Lake).......................0.29
  Munster 2NNW (Lake)..........................0.27
  Schererville 1E (Lake).......................0.27
  Griffith 1N (Lake)...........................0.26
  St. John (Lake)..............................0.25
  Dyer 1WNW (Lake).............................0.23

Other NWS Office Recaps

• Central Iowa (NWS Des Moines)
• Eastern Iowa and Northwest Illinois  (NWS Quad Cities)
• Southern Wisconsin  (NWS Milwaukee)
• Central Illinois  (NWS Central Illinois)
• Northern Indiana  (NWS Northern Indiana)
• Central Indiana  (NWS Indianapolis)
• National Summary (NWS Storm Prediction Center)
• NWS Chicago Past Events Page