Alert archive / Illinois / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 81, NWS Quad Cities, IA
NWS Quad Cities, IA issued this severe thunderstorm warning at Aug 11, 2021, 8:07 AM CDT for 4 counties in Illinois. It was in force for 53 min. 6 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
- Aug 11, 2021, 8:07 AM CDT (13:07 UTC)
- Expired
- Aug 11, 2021, 9:00 AM CDT
- In force
- 53 min
- Issued by
- NWS Quad Cities, IA
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Bureau County, IL, Henry County, IL, Rock Island County, IL, Whiteside County, IL
The radar
The Quad Cities radar (KDVN), 84 km from the middle of the area, began a volume at 13:11 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 |
|---|---|---|---|
| Aug 11, 8:10 AM CDT | TSTM WND DMG | 1 Wsw Geneseo, IL | REPORT FROM MPING: 3-INCH TREE LIMBS BROKEN; POWER POLES BROKEN. |
| Aug 11, 8:15 AM CDT | TSTM WND DMG | Geneseo, IL | SEVERAL TREE LIMBS DOWN (3 TO 4 INCH) AND POWER OUT. |
| Aug 11, 8:35 AM CDT | TSTM WND DMG | Ohio, IL | POLE BARN DESTROYED FROM THE STRAIGHT LINE WINDS, WITH POSTS RIPPED OUT OF THE GROUND. |
| Aug 11, 8:40 AM CDT | TSTM WND DMG | Ohio, IL | TREE DOWN AND CORN FLATTENED. 2-4 INCH BRANCHES ALSO DOWN. ESTIMATED 60 MPH OR GREATER. |
| Aug 11, 8:45 AM CDT | TSTM WND DMG | Morrison, IL | LARGE TREE BRANCH DOWN, APPROXIMATELY 15 TO 18 INCHES IN DIAMETER. |
| Aug 11, 8:50 AM CDT | TSTM WND DMG | La Moille, IL | VERY HIGH WINDS LEAD TO MANY 2 TO 6 INCH LIMBS DOWN. |
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, 1.1 hours before the alert went out and 77 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
- 2852 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 1040 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- 170 m²/s²
- 0-3 km storm-relative helicity
- 193 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.7
The text
As transmitted.
469
WUUS53 KDVN 111307
SVRDVN
ILC011-073-161-195-111400-
/O.NEW.KDVN.SV.W.0081.210811T1307Z-210811T1400Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Quad Cities IA/IL
807 AM CDT Wed Aug 11 2021
The National Weather Service in the Quad Cities has issued a
* Severe Thunderstorm Warning for...
Northeastern Rock Island County in northwestern Illinois...
Whiteside County in northwestern Illinois...
Henry County in northwestern Illinois...
Bureau County in north central Illinois...
* Until 900 AM CDT.
* At 806 AM CDT, severe thunderstorms were located along a line
extending from near Garden Plain to near Altona, moving east at 45
mph. In additionl strong gradient winds are occuring behind the
storms and will also result in winds to 60 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
* Severe thunderstorms will be near...
Erie, Garden Plain and Albany around 810 AM CDT.
Morrison, Prophetstown and Lyndon around 820 AM CDT.
Other locations in the path of these severe thunderstorms include
Kewanee, Rock Falls, Coleta, Emerson, Sterling, Sheffield, Buda,
Wyanet, Tiskilwa, Princeton and Bureau Junction.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
sturdy building.
&&
LAT...LON 4132 8924 4130 8933 4123 8936 4123 8947
4121 8947 4117 8964 4123 8964 4123 8987
4115 8987 4115 9027 4178 9024 4193 8980
4193 8963 4159 8963 4158 8922
TIME...MOT...LOC 1306Z 250DEG 38KT 4174 9016 4115 9019
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin4 follow-up statements
599
WWUS53 KDVN 111313
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
813 AM CDT Wed Aug 11 2021
ILC011-073-161-195-111400-
/O.CON.KDVN.SV.W.0081.000000T0000Z-210811T1400Z/
Rock Island IL-Whiteside IL-Henry IL-Bureau IL-
813 AM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 AM CDT
FOR NORTHEASTERN ROCK ISLAND...WHITESIDE...HENRY AND BUREAU
COUNTIES...
At 813 AM CDT, severe thunderstorms were located along a line
extending from near Garden Plain to near Altona, moving east at 45
mph. An area of strong winds will continue behind the storms, with
an extended period of near 60 mph winds expected to last up to 2
hours.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
These severe storms will be near...
Prophetstown around 820 AM CDT.
Morrison and Lyndon around 825 AM CDT.
Other locations in the path of these severe thunderstorms include
Kewanee, Coleta, Emerson, Rock Falls, Sterling, Sheffield, Buda and
Wyanet.
LAT...LON 4132 8924 4130 8933 4123 8936 4123 8947
4121 8947 4117 8964 4123 8964 4123 8987
4115 8987 4115 9027 4178 9024 4193 8980
4193 8963 4159 8963 4158 8922
TIME...MOT...LOC 1313Z 250DEG 38KT 4176 9009 4117 9012
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin679
WWUS53 KDVN 111327
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
827 AM CDT Wed Aug 11 2021
ILC011-073-161-195-111400-
/O.CON.KDVN.SV.W.0081.000000T0000Z-210811T1400Z/
Rock Island IL-Whiteside IL-Henry IL-Bureau IL-
827 AM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 AM CDT
FOR NORTHEASTERN ROCK ISLAND...WHITESIDE...HENRY AND BUREAU
COUNTIES...
At 826 AM CDT, severe thunderstorms were located along a line
extending from Morrison to near Kewanee, moving east at 45 mph.
An area of strong winds will continue behind the storms, with an
extended period of near 60 mph winds expected to last up to 2 hours.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
These severe storms will be near...
Morrison and Lyndon around 830 AM CDT.
Other locations in the path of these severe thunderstorms include
Rock Falls, Coleta, Emerson, Sterling, Sheffield, Buda, Wyanet,
Tiskilwa, Princeton, Bureau Junction, Hennepin, Spring Valley and
DePue.
LAT...LON 4132 8924 4130 8933 4123 8936 4123 8947
4121 8947 4117 8964 4123 8964 4123 8987
4115 8987 4115 9027 4178 9024 4193 8980
4193 8963 4159 8963 4158 8922
TIME...MOT...LOC 1326Z 250DEG 38KT 4180 8995 4121 8998
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
Ervin697
WWUS53 KDVN 111349
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
849 AM CDT Wed Aug 11 2021
ILC011-073-161-195-111400-
/O.CON.KDVN.SV.W.0081.000000T0000Z-210811T1400Z/
Rock Island IL-Whiteside IL-Henry IL-Bureau IL-
849 AM CDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 AM CDT
FOR NORTHEASTERN ROCK ISLAND...WHITESIDE...HENRY AND BUREAU
COUNTIES...
At 848 AM CDT, severe thunderstorms were located along a line
extending from near Sterling to near Buda, moving east at 45 mph.
An area of strong winds will continue behind the storms, with an
extended period of near 60 mph winds expected to last up to 2 hours.
HAZARD...75 mph wind gusts with storm moving through Bureau county.
SOURCE...Trained weather spotters.
IMPACT...Expect considerable tree damage. Damage is likely to mobile
homes, roofs, and outbuildings.
Locations impacted include...
Princeton, Bureau Junction, Hennepin, DePue and Spring Valley.
LAT...LON 4132 8924 4130 8933 4123 8936 4123 8947
4121 8947 4117 8964 4123 8964 4123 8987
4115 8987 4115 9027 4178 9024 4193 8980
4193 8963 4159 8963 4158 8922
TIME...MOT...LOC 1348Z 250DEG 38KT 4187 8968 4128 8971
THUNDERSTORM DAMAGE THREAT...CONSIDERABLE
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...70 MPH
$$
Ervin411
WWUS53 KDVN 111356
SVSDVN
Severe Weather Statement
National Weather Service Quad Cities IA/IL
856 AM CDT Wed Aug 11 2021
ILC011-073-161-195-111404-
/O.EXP.KDVN.SV.W.0081.000000T0000Z-210811T1400Z/
Rock Island IL-Whiteside IL-Henry IL-Bureau IL-
856 AM CDT Wed Aug 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN ROCK ISLAND...
WHITESIDE...HENRY AND BUREAU COUNTIES WILL EXPIRE AT 900 AM CDT...
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire. However gusty
winds are still possible with these thunderstorms. Severe
thunderstorm warnings continue for portions of Bureau, Putnam, and
eastern Whiteside county.
An area of strong winds will continue behind the storms, with an
extended period of near 60 mph winds expected to last up to one
hour. A High Wind Warning continues through 10 AM for winds up to
60 MPH.
To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
the Quad Cities.
LAT...LON 4132 8924 4130 8933 4123 8936 4123 8947
4121 8947 4117 8964 4123 8964 4123 8987
4115 8987 4115 9027 4178 9024 4193 8980
4193 8963 4159 8963 4158 8922
TIME...MOT...LOC 1354Z 250DEG 38KT 4189 8960 4130 8963
$$
ErvinThe office that day
Everything else NWS Quad Cities, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 5:56 AM CDT | Severe Thunderstorm Warning | DVN | Hancock | 19 min |
| Aug 11, 6:24 AM CDT | Special Weather Statement | DVN | McDonough | 36 min |
| Aug 11, 6:24 AM CDT | Severe Thunderstorm Warning | DVN | Henderson, Warren | 22 min |
| Aug 11, 6:38 AM CDT | Severe Thunderstorm Warning | DVN | Henderson, Mercer, Warren | 37 min |
| Aug 11, 6:59 AM CDT | Flash Flood Warning | DVN | Hancock, Henderson | 3 hr |
| Aug 11, 7:32 AM CDT | Special Weather Statement | DVN | Rock Island | 28 min |
| Aug 11, 7:55 AM CDT | Special Weather Statement | DVN | Bureau, Henry, Whiteside | 65 min |
| Aug 11, 8:16 AM CDT | High Wind Warning | DVN | Henderson, Henry, Mercer, Rock Island, Warren, Whiteside | 104 min |
| Aug 11, 8:33 AM CDT | Severe Thunderstorm Warning | DVN | Bureau, Putnam, Whiteside | 57 min |
| Aug 11, 9:46 AM CDT | Areal Flood Warning | DVN | Henderson | 3 hr |
| Aug 11, 9:59 AM CDT | Special Weather Statement | DVN | McDonough | 31 min |
| Aug 11, 10:45 AM CDT | Special Weather Statement | DVN | Henderson, Warren | 30 min |
| Aug 11, 10:57 AM CDT | Severe Thunderstorm Warning | DVN | Henderson, McDonough, Warren | 33 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.