Alert archive / Illinois / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 1, NWS Chicago, IL
NWS Chicago, IL issued this severe thunderstorm warning at Mar 20, 2011, 2:16 PM CDT for Winnebago County, Illinois. It was in force for 29 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Mar 20, 2011, 2:16 PM CDT (19:16 UTC)
- Expired
- Mar 20, 2011, 2:45 PM CDT
- In force
- 29 min
- Issued by
- NWS Chicago, IL
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 50.0 mph
County Winnebago County, IL
The radar
The Milwaukee radar (KMKX), 86 km from the middle of the area, began a volume at 19:15 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.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 7.3 hours before the alert went out and 136 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 885 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 528 m²/s²
- 0-3 km storm-relative helicity
- 614 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Chicago, IL wrote its last area forecast discussion before this severe thunderstorm warning went out at Mar 20, 1:59 PM CDT, 17 minutes earlier.
Area forecast discussion, Mar 20, 1:59 PM CDT, 17 minutes before
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</html>Hazardous weather outlook, Mar 20, 11:21 AM CDT, 2 hours 55 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 1121 AM CDT SUN MAR 20 2011 ILZ003>006-008-010>014-019>023-032-033-039-INZ001-002-010-011-019- 211630- WINNEBAGO-BOONE-MCHENRY-LAKE ILLINOIS-OGLE-LEE-DE KALB-KANE- DUPAGE-COOK-LA SALLE-KENDALL-GRUNDY-WILL-KANKAKEE-LIVINGSTON- IROQUOIS-FORD-LAKE INDIANA-PORTER-NEWTON-JASPER-BENTON- 1121 AM CDT SUN MAR 20 2011 /1221 PM EDT SUN MAR 20 2011/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL ILLINOIS... NORTHEAST ILLINOIS AND NORTHWEST INDIANA. .DAY ONE...THIS AFTERNOON AND TONIGHT. WEATHER HAZARDS EXPECTED: THUNDERSTORMS...SOME COULD PRODUCE: PEA TO QUARTER SIZED HAIL WIND GUSTS TO 60 MPH OCCASIONAL CLOUD TO GROUND LIGHTNING AREAS AFFECTED AND TIMING: SHOWERS AND THUNDERSTORMS ARE LIKELY ACROSS NORTHERN ILLINOIS THIS MORNING AND ACROSS THE ENTIRE FORECAST AREA THIS AFTERNOON AND EVENING. DISCUSSION: THUNDERSTORMS GENERALLY ARE EXPECTED TO REMAIN BELOW SEVERE LEVELS TODAY...OCCASIONALLY PRODUCING PEA SIZED HAIL...BUT THERE IS A POSSIBILITY THAT A FEW STORMS COULD BECOME SEVERE TOWARD LATE AFTERNOON OR EVENING. A LOW PRESSURE SYSTEM PASSING NORTH OF THE AREA WILL DRAG A COLD FRONT THROUGH OVERNIGHT. INCREASING INSTABILITY AND LIFT AHEAD OF THE FRONT THIS EVENING...TOGETHER WITH THE STRONG WIND FIELD ALREADY IN PLACE...COULD SUPPORT SUPERCELLS WITH LARGER HAIL AND STRONG WIND GUSTS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TOMORROW NIGHT INTO TUESDAY. WITH SEVERAL CHANCES FOR SHOWERS AND THUNDERSTORMS THIS WEEK...TOTAL RAINFALL AMOUNTS COULD REACH ONE TO TWO INCHES WITH LOCALLY HIGHER AMOUNTS POSSIBLE. CONDITIONS WILL NEED TO BE MONITORED FOR RISES ON AREA STREAMS AND RIVERS WHICH COULD LEAD TO RENEWED FLOODING PROBLEMS. .SPOTTER INFORMATION STATEMENT... SPOTTERS MAY BE NEEDED LATER THIS AFTERNOON AND EVENING. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO LMZ740>745-211630- WINTHROP HARBOR TO WILMETTE HARBOR- WILMETTE HARBOR TO NORTHERLY ISLAND- NORTHERLY ISLAND TO CALUMET HARBOR-CALUMET HARBOR TO GARY- GARY TO BURNS HARBOR-BURNS HARBOR TO MICHIGAN CITY- 1121 AM CDT SUN MAR 20 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE ILLINOIS NEARSHORE WATERS OF LAKE MICHIGAN AND THE INDIANA NEARSHORE WATERS OF LAKE MICHIGAN. .DAY ONE...THIS AFTERNOON AND TONIGHT. STRONG SOUTHERLY WINDS WILL LEAD TO HAZARDOUS CONDITIONS FOR SMALL CRAFT TODAY AND TONIGHT FOR BOTH THE ILLINOIS AND INDIANA NEARSHORE WATERS. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY AND TONIGHT. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MONDAY NIGHT INTO TUESDAY. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO LMZ080-261-362-364-366-563-565-567-669-671-673-675-777-779-868- 870-872-874-876-878-211630- LAKE MICHIGAN FROM MICHIGAN CITY IN TO ST. JOSEPH MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SEUL CHOIX POINT TO ROCK ISLAND PASSAGE 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN SOUTH OF A LINE FROM SEUL CHOIX POINT TO THE MACKINAC BRIDGE AND NORTH OF A LINE FROM CHARLEVOIX MI TO SOUTH FOX ISLAND 5 NM OFFSHORE- LAKE MICHIGAN FROM CHARLEVOIX TO POINT BETSIE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM POINT BETSIE TO MANISTEE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM ROCK ISLAND PASSAGE TO STURGEON BAY WI- LAKE MICHIGAN FROM STURGEON BAY TO TWO RIVERS WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM TWO RIVERS TO SHEBOYGAN WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SHEBOYGAN TO PORT WASHINGTON WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM PORT WASHINGTON TO NORTH POINT LIGHT WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM NORTH POINT LIGHT TO WIND POINT WI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WIND POINT WI TO WINTHROP HARBOR IL 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WINTHROP HARBOR TO WILMETTE HARBOR IL 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WILMETTE HARBOR IL TO MICHIGAN CITY IN 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM PENTWATER TO MANISTEE MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM WHITEHALL TO PENTWATER MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM GRAND HAVEN TO WHITEHALL MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM HOLLAND TO GRAND HAVEN MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM SOUTH HAVEN TO HOLLAND MI 5 NM OFFSHORE TO MID LAKE- LAKE MICHIGAN FROM ST. JOSEPH TO SOUTH HAVEN MI 5 NM OFFSHORE TO MID LAKE- 1121 AM CDT SUN MAR 20 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE OPEN WATERS OF LAKE MICHIGAN. .DAY ONE...THIS AFTERNOON AND TONIGHT. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE TODAY AND TONIGHT. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE MONDAY NIGHT INTO TUESDAY MAINLY OVER THE SOUTHERN PORTIONS OF THE LAKE. && COMPLETE FORECAST INFORMATION IS AVAILABLE ON THE NWS CHICAGO WEBPAGE: WEATHER.GOV/CHICAGO LENNING
In the hours before
Local storm report, Mar 20, 1:43 PM CDT, 33 minutes before
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</html>Local storm report, Mar 20, 1:49 PM CDT, 27 minutes before
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</html>Local storm report, Mar 20, 1:51 PM CDT, 25 minutes before
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</html>Local storm report, Mar 20, 1:52 PM CDT, 24 minutes before
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</html>Local storm report, Mar 20, 1:57 PM CDT, 19 minutes before
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</html>Local storm report, Mar 20, 2:04 PM CDT, 12 minutes before
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</html>The office that day
Everything else NWS Chicago, IL issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 20, 1:29 PM CDT | Areal Flood Advisory | LOT | Boone, Ogle, Winnebago | 4 hr |
| Mar 20, 2:51 PM CDT | Special Weather Statement | LOT | Boone, McHenry | 24 min |
| Mar 20, 3:07 PM CDT | Areal Flood Advisory | LOT | Boone, Cook, DeKalb, Kane, Lake, McHenry and 1 more | 7 hr |
| Mar 20, 3:16 PM CDT | Special Weather Statement | LOT | Lake, McHenry | 44 min |
| Mar 20, 3:21 PM CDT | Special Marine Warning | LOT | 84 min | |
| Mar 20, 4:04 PM CDT | Special Weather Statement | LOT | Lake | 26 min |
| Mar 20, 4:30 PM CDT | Special Weather Statement | LOT | Lake | 15 min |
| Mar 20, 4:42 PM CDT | Special Marine Warning | LOT | 63 min | |
| Mar 20, 6:11 PM CDT | Special Marine Warning | LOT | 49 min |
Nearby
Severe Thunderstorm Warnings in Illinois, 2011Every severe thunderstorm warning in 2011
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.