Alert archive / Illinois / Tornado Watches in 2011
Tornado Watch 373
The Storm Prediction Center issued this tornado watch at May 25, 2011, 2:31 PM CDT for 39 counties in Illinois; 5 counties in Iowa; Clark County, Scotland County, Missouri. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 25, 2011, 2:31 PM CDT (19:31 UTC)
- Expired
- May 25, 2011, 10:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 46 counties
Des Moines County, IA, Henry County, IA, Lee County, IA, Louisa County, IA, Van Buren County, IA, Bureau County, IL, Cass County, IL, Champaign County, IL, DeKalb County, IL, DeWitt County, IL, Ford County, IL, Fulton County, IL, Grundy County, IL, Hancock County, IL, Henderson County, IL, Henry County, IL, Iroquois County, IL, Kankakee County, IL, Kendall County, IL, Knox County, IL, LaSalle County, IL, Lee County, IL, Livingston County, IL, Logan County, IL, Macon County, IL, Marshall County, IL, Mason County, IL, McDonough County, IL, McLean County, IL, Menard County, IL, Mercer County, IL, Morgan County, IL, Peoria County, IL, Piatt County, IL, Putnam County, IL, Sangamon County, IL, Schuyler County, IL, Scott County, IL, Stark County, IL, Tazewell County, IL, Vermilion County, IL, Warren County, IL, Will County, IL, Woodford County, IL, Clark County, MO, Scotland County, MO
The radar
The Quad Cities radar (KDVN), 86 km from the middle of the area, began a volume at 19:34 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 SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 50%
- One or more EF2 to EF5 tornadoes
- 30%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
44 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 25, 2:44 PM CDT | Severe Thunderstorm Warning | ILX | Edgar, Vermilion | 38 min |
| May 25, 3:34 PM CDT | Severe Thunderstorm Warning | DVN | Clark, Scotland | 56 min |
| May 25, 3:47 PM CDT | Tornado Warning | ILX | Cass, Morgan, Scott | 43 min |
| May 25, 4:02 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Sangamon | 58 min |
| May 25, 4:08 PM CDT | Severe Thunderstorm Warning | DVN | Van Buren | 52 min |
| May 25, 4:17 PM CDT | Tornado Warning | ILX | Christian, Sangamon | 25 min |
| May 25, 4:29 PM CDT | Severe Thunderstorm Warning | ILX | Cass, Fulton, Mason, Morgan, Schuyler | 61 min |
| May 25, 4:33 PM CDT | Severe Thunderstorm Warning | ILX | Cass, Menard, Morgan, Sangamon | 57 min |
| May 25, 4:33 PM CDT | Flash Flood Warning | DVN | Clark, Scotland | 3 hr |
| May 25, 4:35 PM CDT | Tornado Warning | DVN | Hancock | 40 min |
| May 25, 4:55 PM CDT | Flash Flood Warning | DVN | Des Moines, Henry, Jefferson, Lee, Van Buren | 5 hr |
| May 25, 4:57 PM CDT | Severe Thunderstorm Warning | ILX | Christian, Logan, Menard, Sangamon | 51 min |
| May 25, 5:00 PM CDT | Severe Thunderstorm Warning | ILX | Douglas, Macon, Moultrie, Piatt, Shelby | 60 min |
| May 25, 5:01 PM CDT | Flash Flood Warning | ILX | Cass, Fulton, Schuyler | 3 hr |
| May 25, 5:05 PM CDT | Severe Thunderstorm Warning | DVN | Henderson, Mercer | 40 min |
| May 25, 5:08 PM CDT | Flash Flood Warning | ILX | Christian, Sangamon | 3 hr |
| May 25, 5:11 PM CDT | Tornado Warning | DVN | Mercer | 23 min |
| May 25, 5:19 PM CDT | Severe Thunderstorm Warning | ILX | Fulton, Logan, Mason, Menard, Tazewell | 35 min |
| May 25, 5:30 PM CDT | Severe Thunderstorm Warning | DVN | Henderson, Henry, Mercer, Warren | 45 min |
| May 25, 5:34 PM CDT | Flash Flood Warning | DVN | Henderson, Mercer, Warren | 4 hr |
| May 25, 5:37 PM CDT | Severe Thunderstorm Warning | ILX | Macon, Piatt, Shelby | 38 min |
| May 25, 5:42 PM CDT | Severe Thunderstorm Warning | ILX | DeWitt, McLean, Macon, Piatt | 37 min |
| May 25, 5:45 PM CDT | Severe Thunderstorm Warning | ILX | Fulton, Knox, McLean, Peoria, Tazewell, Woodford | 60 min |
| May 25, 5:51 PM CDT | Tornado Warning | ILX | DeWitt, McLean | 24 min |
| May 25, 5:58 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Douglas, Piatt | 47 min |
| May 25, 6:12 PM CDT | Tornado Warning | ILX | McLean | 40 min |
| May 25, 6:15 PM CDT | Severe Thunderstorm Warning | ILX | Knox, McLean, Marshall, Peoria, Stark, Woodford | 40 min |
| May 25, 6:19 PM CDT | Flash Flood Warning | ILX | Knox | 4 hr |
| May 25, 6:27 PM CDT | Severe Thunderstorm Warning | ILX | Champaign | 33 min |
| May 25, 6:27 PM CDT | Tornado Warning | LOT | LaSalle, Livingston | 24 min |
| May 25, 6:31 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Putnam | 44 min |
| May 25, 6:42 PM CDT | Severe Thunderstorm Warning | ILX | Champaign, Coles, Douglas, Moultrie, Piatt | 33 min |
| May 25, 6:53 PM CDT | Tornado Warning | ILX | Champaign, Piatt | 37 min |
| May 25, 7:01 PM CDT | Severe Thunderstorm Warning | LOT | Ford, Iroquois, Livingston | 59 min |
| May 25, 7:08 PM CDT | Tornado Warning | ILX | Champaign, Vermilion | 52 min |
| May 25, 7:11 PM CDT | Flash Flood Warning | DVN | Bureau, Henry, Putnam | 4 hr |
| May 25, 7:11 PM CDT | Tornado Warning | ILX | Champaign, Clark, Coles, Crawford, Cumberland, Douglas and 3 more | 49 min |
| May 25, 7:36 PM CDT | Flash Flood Warning | DVN | Bureau | 3 hr |
| May 25, 7:37 PM CDT | Severe Thunderstorm Warning | LOT | Iroquois, Kankakee | 53 min |
| May 25, 7:46 PM CDT | Flash Flood Warning | LOT | DeKalb, LaSalle, Lee | 5 hr |
| May 25, 7:50 PM CDT | Severe Thunderstorm Warning | LOT | Iroquois | 70 min |
| May 25, 7:53 PM CDT | Tornado Warning | ILX | Vermilion | 37 min |
| May 25, 7:56 PM CDT | Tornado Warning | ILX | Clark, Edgar, Vermilion | 34 min |
| May 25, 8:09 PM CDT | Flash Flood Warning | LOT | Kankakee, Will | 6 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Lincoln, IL (KILX), launched 12:00Z, 7.5 hours before the alert went out and 165 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
- 1832 J/kg
- Mixed-layer CIN
- -18 J/kg
- Mixed-layer LCL
- 561 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- 253 m²/s²
- 0-3 km storm-relative helicity
- 222 m²/s²
- Significant tornado parameter
- 1.6
- Supercell composite
- 10.1
The text
As transmitted, in the capitals the NWS used until 2016.
316
WWUS20 KWNS 251936
SEL3
SPC WW 251936
IAZ000-ILZ000-MOZ000-260300-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 373
NWS STORM PREDICTION CENTER NORMAN OK
235 PM CDT WED MAY 25 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
FAR SOUTHEAST IOWA
CENTRAL AND NORTHERN ILLINOIS
FAR NORTHEAST MISSOURI
EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 235 PM UNTIL
1000 PM CDT.
TORNADOES...HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 70 MILES NORTHEAST OF MOLINE
ILLINOIS TO 45 MILES WEST OF ALTON ILLINOIS. FOR A COMPLETE
DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE
(WOUS64 KWNS WOU3).
REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.
OTHER WATCH INFORMATION...CONTINUE...WW 368...WW 369...WW
370...WW 371...WW 372...
DISCUSSION...CLUSTER OF SEVERE STORMS --INCLUDING TORNADIC
SUPERCELLS-- OVER NERN MO WILL CONTINUE TO DEVELOP NEWD INTO AREA
THIS AFTERNOON IN ADVANCE OF DEEP-LAYER CYCLONE MOVING INTO NRN MO.
RELATIVELY CLOUD-FREE SKIES HAVE ALLOWED TEMPERATURES TO WARM
THROUGH THE 70S. WHEN COUPLED WITH BOUNDARY LAYER DEWPOINTS IN THE
MID 60S AND COOLING MIDLEVEL TEMPERATURES ARE RESULTING IN A
MODERATELY UNSTABLE ENVIRONMENT WITH MLCAPE OF 1000-2000 J/KG.
GIVEN VERTICALLY VEERING WIND PROFILES AND AMBIENT VORTICITY INVOF
WARM FRONT...SETUP WILL BE SUPPORTIVE OF SUPERCELLS CAPABLE OF
TORNADOES...LARGE HAIL AND DAMAGING WINDS.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
500. MEAN STORM MOTION VECTOR 22035.
...MEADSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 25, 12:48 AM CDT | Mesoscale Discussion | SPC | Adams, Alexander, Bond, Brown, Calhoun, Cass and 23 more | 57 min |
| May 25, 1:22 AM CDT | Tornado Watch | SPC | Adams, Brown, Calhoun, Cass, Fulton, Greene and 16 more | 7 hr |
| May 25, 4:58 AM CDT | Mesoscale Discussion | SPC | Bond, Brown, Calhoun, Cass, Champaign, Christian and 45 more | 92 min |
| May 25, 5:46 AM CDT | Tornado Watch | SPC | Bond, Champaign, Christian, Clark, Clay, Clinton and 35 more | 7 hr |
| May 25, 7:31 AM CDT | Mesoscale Discussion | SPC | Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more | 59 min |
| May 25, 7:48 AM CDT | Mesoscale Discussion | SPC | Champaign, Clark, Clay, Clinton, Coles, Crawford and 18 more | 87 min |
| May 25, 8:33 AM CDT | Mesoscale Discussion | SPC | Champaign, DeWitt, Douglas, Edgar, Ford, Iroquois and 3 more | 87 min |
| May 25, 10:18 AM CDT | Mesoscale Discussion | SPC | Bond, Clark, Clay, Clinton, Crawford, Cumberland and 12 more | 57 min |
| May 25, 10:37 AM CDT | Tornado Watch | SPC | Adams, Brown, Pike | 7 hr |
| May 25, 11:02 AM CDT | Mesoscale Discussion | SPC | Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 13 more | 28 min |
| May 25, 11:09 AM CDT | Tornado Watch | SPC | Alexander, Bond, Calhoun, Christian, Clark, Clay and 41 more | 10 hr |
| May 25, 2:32 PM CDT | Mesoscale Discussion | SPC | Calhoun, Greene, Jersey, Macoupin, Pike, Scott | 58 min |
| May 25, 3:10 PM CDT | Mesoscale Discussion | SPC | Alexander, Franklin, Gallatin, Hardin, Jackson, Johnson and 6 more | 95 min |
| May 25, 5:48 PM CDT | Mesoscale Discussion | SPC | Bureau, Champaign, DeKalb, DeWitt, Douglas, Ford and 19 more | 117 min |
| May 25, 6:25 PM CDT | Mesoscale Discussion | SPC | Alexander, Clay, Clinton, Edwards, Franklin, Gallatin and 20 more | 2 hr |
| May 24, 7:07 PM CDT | Mesoscale Discussion | SPC | Andrew, Barton, Bates, Buchanan, Cass, Cedar and 14 more | 53 min |
| May 24, 7:26 PM CDT | Tornado Watch | SPC | Adair, Barry, Barton, Bates, Benton, Buchanan and 48 more | 7 hr |
| May 24, 7:42 PM CDT | Mesoscale Discussion | SPC | McDonald | 63 min |
| May 24, 11:24 PM CDT | Mesoscale Discussion | SPC | Benton, Camden, Christian, Cooper, Dallas, Douglas and 15 more | 96 min |
| May 25, 9:54 AM CDT | Mesoscale Discussion | SPC | Benton, Butler, Camden, Carter, Christian, Dallas and 24 more | 96 min |
| May 25, 11:52 AM CDT | Mesoscale Discussion | SPC | Dunklin, Pemiscot | 83 min |
| May 25, 12:28 PM CDT | Tornado Watch | SPC | Dunklin, Pemiscot | 8 hr |
| May 25, 1:28 PM CDT | Mesoscale Discussion | SPC | Adair, Audrain, Boone, Caldwell, Callaway, Camden and 44 more | 92 min |
| May 25, 2:56 PM CDT | Mesoscale Discussion | SPC | Dunklin, Pemiscot | 94 min |
| May 25, 5:56 PM CDT | Mesoscale Discussion | SPC | Dunklin, Pemiscot | 64 min |
Nearby
Tornado Watches in Illinois, 2011Tornado Watches in Iowa, 2011Tornado Watches in Missouri, 2011Every tornado watch 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.