June 20, 2021: Tornado, Damaging Winds, and Hail

Overview

Severe thunderstorms developed across Iowa, Illinois and Missouri on Sunday, June 20th. Early in the morning, an MCS from the night before moved into our area along a stationary boundary and brought widespread rain showers to the area. This died off early in the day and then some clear skies moved in, providing some surface heating ahead of an approaching cold front. Ahead of this front, several discrete supercell thunderstorms formed, which posed a threat for tornadoes, hail, and severe wind gusts. Later in the day. these supercells generally grew upscale into a line of thunderstorms with embedded supercell structures. A tornado was spotted near Bernard, Iowa and lead to some damage to trees and farm outbuildings. Otherwise, severe winds reports and a few hail reports resulted from these storms. The severe threat continued on after our area heavily impacted some suburbs near Chicago. Please see NWS Chicago's webpage for more information.

Surrounding Office Summaries

Tornado near Bernard, Iowa. (Courtesy Sabra Lyons)

Tornado
Radar
Storm Reports
Rainfall
Environment

Tornadoes:

Tornado #1 - South of Bernard, IA
N. Jackson Co. into S. Dubuque Co.

Date	06/20/2021
Time (Local)	8:06 PM to 8:12 PM
EF Rating	EF1
Est. Peak Winds	90-100 MPH
Path Length	3.1 miles
Max Width	30 yards
Injuries/Deaths	0/0
Summary: A brief tornado caused damage to trees and farm outbuildings about 1.5 miles SW of Bernard, IA to about 2 miles east of Bernard.

Track Map

/source/dvn/DamageKML/2021/storm_survey.kmz

	Damage Survey Photos

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

Click Here For An Interactive Radar Loop (Courtesy IEM)

Storm Reports

Interactive Storm Report Map (IEM)	SPC Storm Reports


Half-Dollar Sized Hail Near Washington, IA. Photo courtesy: Nick Stewart


PRELIMINARY LOCAL STORM REPORT...SUMMARY NATIONAL WEATHER SERVICE QUAD CITIES IA IL 1126 PM CDT SUN JUN 20 2021 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 1000 PM TSTM WND GST RAPIDS CITY 41.58N 90.34W 06/20/2021 E50 MPH ROCK ISLAND IL PUBLIC 1028 PM TSTM WND GST COLCHESTER 40.43N 90.79W 06/20/2021 E60 MPH MCDONOUGH IL TRAINED SPOTTER CORRECTS PREVIOUS TSTM WND GST REPORT FROM COLCHESTER. ALSO A TREE DOWN. 1033 PM TSTM WND DMG 1 SW MACOMB 40.46N 90.70W 06/20/2021 MCDONOUGH IL TRAINED SPOTTER LARGE TREE DOWN ON HIGHWAY 136 BLOCKING THE WEST BOUND LANES. 1034 PM TSTM WND GST MACOMB 40.47N 90.68W 06/20/2021 M60 MPH MCDONOUGH IL EMERGENCY MNGR WIND ESTIMATED. 0908 PM HAIL LANARK 42.10N 89.83W 06/20/2021 M0.25 INCH CARROLL IL TRAINED SPOTTER ALSO WIND GUST TO 45 MPH. 0910 PM TSTM WND DMG LANARK 42.10N 89.83W 06/20/2021 CARROLL IL TRAINED SPOTTER 7-8 INCH DIAMETER BRANCH DOWN FRANKLIN AND HIGH STREETS. 0913 PM HAIL 4 SSE SHANNON 42.09N 89.72W 06/20/2021 M1.25 INCH CARROLL IL TRAINED SPOTTER MARBLE TO 1.25 INCH HAIL. LASTED 4 MINUTES. 1053 PM HEAVY RAIN 1 SW MOUNT CARROLL 42.09N 89.99W 06/20/2021 M2.02 INCH CARROLL IL PUBLIC 0849 PM HAIL WASHINGTON 41.30N 91.69W 06/20/2021 M0.25 INCH WASHINGTON IA AMATEUR RADIO 0859 PM TSTM WND DMG WASHINGTON 41.30N 91.69W 06/20/2021 WASHINGTON IA LAW ENFORCEMENT FEW DOWNED LIMBS, ROOF OFF BASEBALL CLUBHOUSE (OUTBUILDING), UNSPECIFIED DAMAGE AT THE FAIRGROUNDS, POWER OUT IN SPOTS AROUND TOWN. 0903 PM HEAVY RAIN 3 NNE CEDAR RAPIDS 42.01N 91.66W 06/20/2021 M1.48 INCH LINN IA TRAINED SPOTTER 0920 PM HEAVY RAIN 1 WSW LANGWORTHY 42.18N 91.23W 06/20/2021 M1.60 INCH JONES IA PUBLIC 0809 PM TSTM WND DMG 1 NNE GARRY OWEN 42.30N 90.82W 06/20/2021 JACKSON IA EMERGENCY MNGR POWER LINES AND BUILDINGS DOWN ON MCDEVITT LANE. POSSIBLE TORNADO. 0802 PM TSTM WND GST CASCADE 42.30N 91.01W 06/20/2021 M55 MPH DUBUQUE IA EMERGENCY MNGR 1003 PM HEAVY RAIN WEST BURLINGTON 40.82N 91.18W 06/20/2021 M1.50 INCH DES MOINES IA TRAINED SPOTTER UPDATES THE PREVIOUS HEAVY RAIN REPORT FROM WEST BURLINGTON. 0708 PM HAIL 3 NE MANCHESTER AIRPORT 42.53N 91.46W 06/20/2021 E0.25 INCH DELAWARE IA EMERGENCY MNGR ALSO 40-45 MPH WIND GUST. 0720 PM TSTM WND DMG MANCHESTER 42.49N 91.46W 06/20/2021 DELAWARE IA EMERGENCY MNGR BRANCHES DOWN REQUIRING CLEANUP BY THE CITY. 0920 PM TSTM WND GST LOWDEN 41.86N 90.92W 06/20/2021 E50 MPH CEDAR IA CO-OP OBSERVER 45 TO 50 MPH WIND GUST. 0745 PM HEAVY RAIN JESUP 42.48N 92.07W 06/20/2021 M1.30 INCH BUCHANAN IA PUBLIC

Rainfall Reports

Local Rainfall Analysis	Regional Rainfall Analysis

24 hour precipitation reports (in Inches),
for eastern Iowa, northwest and west central Illinois,
and northeast Missouri. Reported between 6 AM and 9 AM,
Monday June 21, 2021.

....IOWA....
Monticello 1 E                   2.20
Manchester                       1.96
Grinnell AWOS 2 SSW              1.69
Anamosa 3 SSW                    1.47
Dubuque #3 7 SW                  1.46
Perry 0 W                        1.39
Dubuque Arpt                     1.36
Independence 1.2 N               1.30
Burlington 0.8 SSE               1.27
Center Junction 2.6 W            1.19
Mount Auburn 2.2 NNW             1.18
Central City 6.7 W               1.16
Center Point 0.6 NNW             1.15
Beaconsfield 1 NNE               1.13
Cedar Rapids 2.7 NE              1.08
Burlington 2S                    1.04
Burlington Arpt                  1.02
Bellevue LD12                    0.95
Independence 0.9 WNW             0.94
Burlington 6.5 SSW               0.91
Parnell 0.1 SSW                  0.85
Maquoketa                        0.82
Camanche 1.2 W                   0.80
Cedar Rapids 5.2 NNE             0.80
Fayette 1 NW                     0.80
Park View 0.2 WSW                0.79
Strawberry Point                 0.78
Washington                       0.77
Iowa City                        0.70
Davenport Arpt                   0.68
Le Claire 1.8 NNE                0.67
Tripoli 0 N                      0.67
Charlotte 1.9 WNW                0.66
Oelwein 1E                       0.65
Marshalltown ASOS 4 N            0.65
Calamus 2.0 NE                   0.65
Elkader 6SSW                     0.60
Sigourney                        0.60
Waterloo ASOS 5 NW               0.59
Fairfax 4.0 NW                   0.58
Marshalltown 1 NW                0.55
Guttenberg Dam 10                0.55
Nichols 3.2 SSW                  0.54
Toledo 3 N                       0.53
Salem 1S                         0.52
Pella 4 N                        0.52
Marion 1.7 NNW                   0.51
Ames US 30 2 SSE                 0.48
Mason City ASOS 6 W              0.46
New London 1.5 SW                0.46
Donnellson                       0.43
North English                    0.42
Mason City 1 NNE                 0.37
Cedar Rapids Arpt                0.37
Williamsburg                     0.37
NWS Johnston* 5 NNW              0.36
Dubuque LD11                     0.35
Le Claire LD14                   0.35
Fort Madison 0.9 NE              0.35
Keokuk LD19                      0.32
West Liberty 0.7 NNW             0.30
Oskaloosa AWOS 9 ESE             0.29
Wellman 4.0 E                    0.28
Brighton                         0.27
De Witt                          0.27
Ottumwa ASOS 6 NNW               0.27
Muscatine 1.4 N                  0.25
Marengo 2.6 SSW                  0.25
Hampton 1 N                      0.24
Muscatine 2N                     0.23
Centerville 0 NE                 0.23
West Branch 2.0 NNW              0.23
Wapello 5.4 SE                   0.21
Iowa City Arpt                   0.21
Ainsworth 7.4 N                  0.19
Wapello 0.2 S                    0.18
Washington 5.8 SW                0.15
North Liberty 0.7 SSW            0.14
Boone 1 SSW                      0.12
Montrose 4.5 NNW                 0.11
Columbus Jct 2 SSW               0.11
Rathbun Reservoir 2 N            0.04
Pella AWOS 2 WSW                 0.00
....ILLINOIS....
Walnut 5.3 ENE                   2.61
Lanark 6.0 E                     2.43
Mount Carroll                    2.28
Steward                          1.56
Mundelein                        1.40
Hanover 0.2 NW                   1.27
Gladstone LD18                   1.20
Ridott 0.1 NE                    1.13
Paw Paw 1 E                      1.10
Atkinson 2.6 NNE                 1.08
Lanark 5.3 N                     1.04
Joliet                           1.03
La Harpe                         0.96
Romeoville                       0.93
Morrison 5.9 SSW                 0.85
Ottawa 4 SW                      0.80
Freeport 1.7 NW                  0.79
Mendota 2 SE                     0.78
Fulton LD13                      0.73
Freeport 2.0 NW                  0.71
Oquawka 0.5 N                    0.70
Mount Carroll 6.8 NNW            0.68
Geneseo 2.0 NW                   0.65
Freeport                         0.62
Dallas City 3.0 SSE              0.62
Elizabeth                        0.62
Rockford ASOS                    0.60
Coleta 1.4 SSW                   0.55
Morrison 3.2 E                   0.53
Sterling 4.9 WSW                 0.51
Princeton                        0.48
New Windsor 2.0 N                0.48
Princeton 1.1 SE                 0.48
Galva 2.7 NE                     0.40
Warsaw 5.8 SE                    0.39
Kewanee 1 E                      0.38
Aledo                            0.37
Stockton 3.4 NNE                 0.35
Aledo 0.4 NE                     0.33
Alpha 2.3 N                      0.33
Alpha 0.7 N                      0.29
St Anne                          0.27
Woodhull 0.3 ESE                 0.25
Davis 0.5 N                      0.25
Bentley                          0.21
Colchester 3.5 NE                0.20
Coal Valley 1.9 SE               0.20
Ill. City LD16 3 WNW             0.20
Coal Valley 2.6 E                0.19
Peoria ASOS                      0.15
Alexis 1 SW                      0.14
New Boston LD17                  0.14
Winslow 4.3 ESE                  0.13
Quincy ASOS                      0.09
Augusta                          0.08
Quad City Arpt                   0.06
Bloomington Airport              0.01
Lincoln NWS                      0.01
Decatur Airport                  0.00
Jacksonville AWOS                0.00
Rochelle AWOS                    0.00
Moline 2.5 W                     0.00
....MISSOURI....
Kahoka 0.6 S                     1.61
Kirksville ASOS                  1.06
Columbia                         0.97
Chillicothe 2 NW                 0.49
Memphis 0.1 S                    0.43
....WISCONSIN....
Beloit-College                   0.55
Madison-ASOS                     0.41
Monroe 1 W                       0.33
Darlington                       0.31
Whitewater                       0.31
Prairie du Chien AWOS            0.30
La Crosse WFO                    0.30
Brodhead 1 SW                    0.27
Watertown-AWOS                   0.24
Allenton-WWTP .6 NW              0.19
....MINNESOTA....
Theilman 1SSW                    1.62
Preston                          0.59

Environment

SPC EVENT REVIEW PAGE: 06/20/2021

SPC Categorical/Tornado/Hail/Wind Outlooks