
Gusty winds are expected from portions of the Mid-Atlantic into the Northeast through the night following the system that brought rain to the area. An atmospheric river will move into the Northwest late today into Saturday bringing moderate to heavy rainfall, mountain snow, windy conditions, and high surf to the area over the weekend. Read More >
Overview
A line of severe thunderstorms moved across northern Illinois late in the evening of May 17th and overnight into the early morning of May 18th. There were numerous reports of damaging winds occurring with these thunderstorms along with a few reports of hail up to the size of golf balls. An EF-1 Tornado also occurred touching down approximately two miles south of Poplar Grove and dissipating approximately 3 miles northwest of Harvard.
Tornadoes:
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Tornado - Capron
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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 |
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Photos:
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| Uprooted trees in Rockton, IL due to severe winds. (Courtesy: Will Wight via Twitter) |
Damaged building in Roscoe/South Beloit, IL due to severe winds. (Courtesy: Will Wight via Twitter) |
Damaged buildings near Capron, IL due to an EF-1 tornado. (NWS Survey) |
Damaged outbuilding/storage garage in Hinckley, IL due to straight-line winds. (Courtesy: Jeff Kilburg) |
Radar:
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| Radar Loop | Velocity Loop with Severe Thunderstorm Warnings (Yellow) and Tornado Warnings (Red) |
Storm Reports
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PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL
812 PM CDT THU MAY 18 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0605 PM TSTM WND DMG MOUNT MORRIS 42.05N 89.43W
05/17/2017 OGLE IL TRAINED SPOTTER
SHEET METAL OFF OF FARM BUILDING. TREES SIX TO TWELVE
INCHES IN DIAMETER DOWN.
0608 PM HEAVY RAIN 5 NW POLO 42.04N 89.65W
05/17/2017 M0.62 INCH OGLE IL CO-OP OBSERVER
RAIN FELL IN 10 MINUTES
0608 PM TSTM WND DMG LEAF RIVER 42.12N 89.40W
05/17/2017 OGLE IL TRAINED SPOTTER
TREES DOWN APPROXIMATELY 12 INCHES IN DIAMETER.
0610 PM TSTM WND GST 6 WNW ROCKFORD 42.29N 89.17W
05/17/2017 M65.00 MPH WINNEBAGO IL BROADCAST MEDIA
WTVO
0615 PM TSTM WND DMG PECATONICA 42.31N 89.36W
05/17/2017 WINNEBAGO IL TRAINED SPOTTER
NUMEROUS MATURE TREES SNAPPED AND UPROOTED. SOME ARE 4
FEET IN DIAMETER, AND SOME ARE ON POWER LINES. POWER
POLES ARE ALSO DOWN, AND A 10 FT BY 8 FT CHICKEN COOP WAS
BLOWN INTO A NEARBY FIELD. PEA SIZED HAIL WAS ALSO
REPORTED.
0617 PM TSTM WND DMG WINNEBAGO 42.27N 89.24W
05/17/2017 WINNEBAGO IL PUBLIC
TANKER TRUCK BLOWN OFF OF US 20
0617 PM HAIL WINNEBAGO 42.27N 89.24W
05/17/2017 M1.75 INCH WINNEBAGO IL BROADCAST MEDIA
HAIL FELL FOR ABOUT 5 MINUTES. HAIL FELL AT WREX.
0618 PM HAIL WINNEBAGO 42.27N 89.24W
05/17/2017 M1.00 INCH WINNEBAGO IL TRAINED SPOTTER
WIND GUSTS ESTIMATED TO 70 MPH.
0630 PM TSTM WND DMG 3 SSW SOUTH BELOIT 42.44N 89.05W
05/17/2017 WINNEBAGO IL PUBLIC
LARGE TREES UPROOTED. TREES 18-20 INCHES IN DIAMETER.
0630 PM TSTM WND DMG 4 NW MACHESNEY PARK 42.39N 89.10W
05/17/2017 WINNEBAGO IL EMERGENCY MNGR
LARGE OUTBUILDING DESTROYED AND ONE WITH ITS ROOF
DAMAGED. NUMEROUS LARGE BRANCHES SNAPPED AND A COUPLE
LARGE TREES DOWNED. REPORTS AND RADAR ARE CONSISTENT WITH
STRAIGHT-LINE WIND DAMAGE OF 90-95 MPH.
0631 PM TSTM WND DMG ROSCOE 42.42N 89.01W
05/17/2017 WINNEBAGO IL TRAINED SPOTTER
MULTIPLE LARGE TREES UPROOTED.
0952 PM TSTM WND DMG DIXON 41.85N 89.48W
05/17/2017 LEE IL EMERGENCY MNGR
MULTIPLE TREES AND WIRES DOWN...INCLUDING LARGE TREES
BLOCKING SOME ROADS. DAMAGE IN A SOUTHWEST TO NORTHEAST
DIRECTION ACROSS TOWN. A PARKED POLICE CAR STORM SPOTTING
ON SOUTH SIDE OF TOWN WAS PUSHED 4 TO 5 FEET BY THE WIND.
1009 PM HAIL ROCKFORD 42.27N 89.06W
05/17/2017 M1.00 INCH WINNEBAGO IL AMATEUR RADIO
QUARTER SIZED HAIL AT ALPINE AND HARRISON IN ROCKFORD.
1019 PM TSTM WND DMG 5 NW MENDOTA 41.60N 89.18W
05/17/2017 LEE IL NWS STORM SURVEY
SPORADIC WIND DAMAGE WAS NOTED OVER EASTERN LEE COUNTY
AND FAR NORTHWEST LASALLE COUNTY. WINDS WERE ESTIMATED TO
90 MPH. SEVERAL WOODEN POWER POLES WERE BROKEN ON ROUTE
52 NORTHWEST OF MENDOTA. SEVERAL HARDWOOD TREES WERE
SNAPPED ON ROUTE 251 NEAR COTTAGE HILL ROAD. AN
IRRIGATION PIVOT WAS TOPPLED IN THE SAME AREA.
1021 PM TORNADO 2 S POPLAR GROVE 42.33N 88.82W
05/17/2017 F1 BOONE IL NWS STORM SURVEY
AN NWS SURVEY TEAM CONFIRMED THAT AN EF-1 TORNADO TOUCHED
DOWN APPROXIMATELY TWO MILES SOUTH OF POPLAR GROVE. THE
TORNADO TRAVELED APPROXIMATELY 10.3 MILES AND LIFTED
THREE MILES NORTHWEST OF HARVARD. THE TORNADO WAS ON THE
GROUND FOR AROUND 13 MINUTES.
1023 PM TSTM WND DMG MENDOTA 41.55N 89.12W
05/17/2017 LA SALLE IL TRAINED SPOTTER
A FEW LARGE TREES DOWNED IN TOWN.
1025 PM HAIL POPLAR GROVE 42.37N 88.82W
05/17/2017 M1.50 INCH BOONE IL AMATEUR RADIO
1027 PM TSTM WND DMG 3 S COMPTON 41.65N 89.09W
05/17/2017 LEE IL NWS STORM SURVEY
MULTIPLE TREES DOWN BLOCKING ROADS ALONG/NEAR ROUTE 251
AND COTTAGE GROVE AND WELLEND ROADS. IRRIGATION PIVOT
TURNED OVER. WIND DAMAGE CONSISTENT WITH 80-90 MPH WINDS.
1037 PM TSTM WND DMG 5 N HARVARD 42.49N 88.62W
05/17/2017 MCHENRY IL NWS STORM SURVEY
NWS STORM SURVEY DETERMINED STRAIGHT-LINE DAMAGE OCCURRED
IN THE UNINCORPORATED COMMUNITY OF BIG FOOT PRAIRIE ALONG
THE ILLINOIS AND WISCONSIN STATE LINE. DAMAGE INCLUDED A
FEW LARGE TREES AND LARGE BRANCHES DOWNED. WIND SPEEDS
WERE ESTIMATED TO BE AROUND 85 MPH.
1045 PM TSTM WND GST DE KALB 41.93N 88.75W
05/17/2017 M49.00 MPH DEKALB IL TRAINED SPOTTER
NORTHERN ILLINOIS UNIVERSITY.
1049 PM TSTM WND DMG DE KALB 41.93N 88.75W
05/17/2017 DE KALB IL TRAINED SPOTTER
ROAD BLOCKED BY A 10 INCH DIAMETER TREE BRANCH.
INTERSECTION OF 7TH STREET AND ROOSEVELT STREET.
1049 PM TSTM WND DMG DE KALB 41.93N 88.75W
05/17/2017 DE KALB IL AMATEUR RADIO
4-6 INCH DIAMETER BRANCHES BLOCKING STREETS
1052 PM TSTM WND DMG HINCKLEY 41.77N 88.64W
05/17/2017 DE KALB IL TRAINED SPOTTER
STRAIGHT-LINE WIND DAMAGE CAUSED ISOLATED TREE DAMAGE AND
DESTROYED A FARM OUTBUILDING.
1055 PM TSTM WND GST PERU 41.34N 89.13W
05/17/2017 M59.00 MPH LA SALLE IL AWOS
1100 PM TSTM WND DMG N UTICA 41.34N 89.01W
05/17/2017 LA SALLE IL LAW ENFORCEMENT
MULTIPLE LARGE TREES DOWN.
1104 PM TSTM WND DMG 4 W PLAINFIELD 41.62N 88.28W
05/17/2017 KENDALL IL TRAINED SPOTTER
LARGE TREE DOWNED ALONG IL HWY 126.
1110 PM TSTM WND DMG NORTH AURORA 41.80N 88.33W
05/17/2017 KANE IL PUBLIC
LARGE TREE DOWN IN A BACKYARD IN NORTH AURORA.
1117 PM TSTM WND GST DUPAGE AIRPORT 41.92N 88.25W
05/17/2017 M66.00 MPH DUPAGE IL ASOS
DPA ASOS GUST TO 66 MPH.
1124 PM TSTM WND DMG 2 NNW CAROL STREAM 41.94N 88.15W
05/17/2017 DUPAGE IL TRAINED SPOTTER
NUMEROUS SMALL BRANCHES DOWN. ALSO A PERIOD OF HAIL, SIZE
UNKNOWN AT THIS TIME. TIME ESTIMATED FROM RADAR.
1127 PM TSTM WND GST CAROL STREAM 41.92N 88.13W
05/17/2017 E55.00 MPH DUPAGE IL TRAINED SPOTTER
1128 PM TSTM WND GST 2 S HANOVER PARK 41.96N 88.14W
05/17/2017 E60.00 MPH DUPAGE IL TRAINED SPOTTER
1226 AM TSTM WND DMG ROMEOVILLE 41.65N 88.09W
05/18/2017 WILL IL NWS EMPLOYEE
DELAYED REPORT. POWERPOLE SNAPPED ON RENWICK ROAD. TIME
ESTIMATED.
1226 AM TSTM WND GST ROMEOVILLE 41.65N 88.09W
05/18/2017 M64.00 MPH WILL IL OFFICIAL NWS OBS
64 MPH GUST AT NWS CHICAGO.
1233 AM TSTM WND DMG LEMONT 41.67N 87.99W
05/18/2017 COOK IL PUBLIC
DELAYED REPORT. LARGE SECTION OF A TREE DOWN. REPORT
RELAYED VIA TWITTER.
0100 AM TSTM WND DMG OAK LAWN 41.72N 87.75W
05/18/2017 COOK IL BROADCAST MEDIA
DELAYED REPORT. 3 TO 4 INCH DIAMETER TREE BRANCH THROUGH
WINDSHIELD AND A 6 INCH DIAMETER BRANCH FELL ON CAR.
SCATTERED TREE LIMBS OF VARYING SIZES DOWN THROUGHOUT
TOWN.
0100 AM TSTM WND DMG HOMETOWN 41.73N 87.73W
05/18/2017 COOK IL TRAINED SPOTTER
DELAYED REPORT. PORTION OF 6 FOOT TALL FENCE DAMAGED.
REPORT RELAYED VIA TWITTER.
0100 AM TSTM WND DMG OAK LAWN 41.72N 87.75W
05/18/2017 COOK IL PUBLIC
NEAR 97TH AND KENNETH IN OAK LAWN. 1 FT DIAMETER BRANCH
FROM A HEALTHY MAPLE TREE DOWN.
0110 AM TSTM WND GST PEOTONE 41.33N 87.80W
05/18/2017 E55.00 MPH WILL IL EMERGENCY MNGR
DELAYED REPORT.
Additional Info:
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