Alert archive / Illinois / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 4, NWS Chicago, IL
NWS Chicago, IL issued this severe thunderstorm warning at Jun 11, 2021, 3:36 PM CDT for DeKalb County, Lee County, Illinois. It was in force for 54 min. 3 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jun 11, 2021, 3:36 PM CDT (20:36 UTC)
- Expired
- Jun 11, 2021, 4:30 PM CDT
- In force
- 54 min
- Issued by
- NWS Chicago, IL
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties DeKalb County, IL, Lee County, IL
The radar
The Chicago radar (KLOT), 73 km from the middle of the area, began a volume at 20:38 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jun 11, 3:44 PM CDT | TSTM WND GST 45 | 3 Sw Clare, IL | PEAK WIND GUST FROM LOCAL MESONET STATION, ID KILMALTA3. |
| Jun 11, 3:52 PM CDT | TSTM WND DMG | Malta, IL | POWER POLES LEANED OVER AND WIRES DOWNED DUE TO THE WIND. TIME ESTIMATED BY RADAR. |
| Jun 11, 4:15 PM CDT | TSTM WND GST 48 | 1 Nnw Cortland, IL | AWOS STATION KDKB DEKALB AIRPORT. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 8.6 hours before the alert went out and 141 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1156 J/kg
- Mixed-layer CIN
- -63 J/kg
- Mixed-layer LCL
- 1370 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 16 m²/s²
- 0-3 km storm-relative helicity
- 31 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
826
WUUS53 KLOT 112036
SVRLOT
ILC037-103-112130-
/O.NEW.KLOT.SV.W.0004.210611T2036Z-210611T2130Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Chicago/Romeoville
336 PM CDT Fri Jun 11 2021
The National Weather Service in Chicago has issued a
* Severe Thunderstorm Warning for...
Northeastern Lee County in north central Illinois...
Northern De Kalb County in north central Illinois...
* Until 430 PM CDT.
* At 335 PM CDT, a severe thunderstorm was located near Esmond, or
10 miles northeast of Rochelle, moving southeast at 25 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage
to roofs, siding, and trees.
* Locations impacted include...
DeKalb, Sycamore, Shabbona, Cortland, Kirkland, Kingston, Malta,
Lee and Fairdale.
Including the following interstates...
I-39 between mile markers 94 and 96.
I-88 between mile markers 83 and 96.
This includes...Northern Illinois University.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4186 8866 4174 8894 4189 8904 4189 8894
4215 8894 4215 8877
TIME...MOT...LOC 2035Z 333DEG 23KT 4203 8892
HAIL...1.00IN
WIND...60MPH
$$
Kluber2 follow-up statements
470
WWUS53 KLOT 112059
SVSLOT
Severe Weather Statement
National Weather Service Chicago/Romeoville
359 PM CDT Fri Jun 11 2021
ILC037-103-112130-
/O.CON.KLOT.SV.W.0004.000000T0000Z-210611T2130Z/
Lee IL-De Kalb IL-
359 PM CDT Fri Jun 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 430 PM CDT
FOR NORTHEASTERN LEE AND NORTHERN DE KALB COUNTIES...
At 358 PM CDT, a severe thunderstorm was located near Malta, or 7
miles northwest of DeKalb, moving southeast at 15 mph.
HAZARD...60 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect wind damage to
roofs, siding, and trees.
Locations impacted include...
DeKalb, Sycamore, Shabbona, Cortland, Kirkland, Malta and Lee.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4186 8866 4174 8894 4189 8900 4189 8894
4209 8894 4207 8874
TIME...MOT...LOC 2058Z 320DEG 12KT 4199 8887
HAIL...1.00IN
WIND...60MPH
$$
Kluber045
WWUS53 KLOT 112124
SVSLOT
Severe Weather Statement
National Weather Service Chicago/Romeoville
424 PM CDT Fri Jun 11 2021
ILC037-103-112133-
/O.EXP.KLOT.SV.W.0004.000000T0000Z-210611T2130Z/
Lee IL-De Kalb IL-
424 PM CDT Fri Jun 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN LEE AND NORTHERN
DE KALB COUNTIES WILL EXPIRE AT 430 PM CDT...
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire. However gusty
winds to 50 mph are still possible with this thunderstorm.
LAT...LON 4186 8866 4174 8894 4189 8900 4189 8894
4209 8894 4207 8874
TIME...MOT...LOC 2123Z 333DEG 23KT 4186 8878
$$
KluberThe office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 1:07 PM CDT | Special Weather Statement | LOT | Boone, Cook, DeKalb, DuPage, Ford, Grundy and 10 more | 113 min |
| Jun 11, 3:17 PM CDT | Severe Thunderstorm Warning | LOT | Ogle | 43 min |
| Jun 11, 4:17 PM CDT | Areal Flood Advisory | LOT | DeKalb, Ogle | 110 min |
| Jun 11, 4:23 PM CDT | Special Weather Statement | LOT | Kane | 52 min |
| Jun 11, 5:10 PM CDT | Special Weather Statement | LOT | LaSalle | 80 min |
| Jun 11, 5:30 PM CDT | Special Weather Statement | LOT | Grundy | 30 min |
Nearby
Severe Thunderstorm Warnings in Illinois, 2021Every severe thunderstorm warning in 2021
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.