Alert archive / Iowa / Tornado Watches in 2014
Tornado Watch 141
The Storm Prediction Center issued this tornado watch at May 11, 2014, 11:53 AM CDT for 7 counties in Illinois; 32 counties in Iowa. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 11, 2014, 11:53 AM CDT (16:53 UTC)
- Expired
- May 11, 2014, 7:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 39 counties
Appanoose County, IA, Benton County, IA, Cedar County, IA, Clarke County, IA, Clinton County, IA, Davis County, IA, Decatur County, IA, Des Moines County, IA, Henry County, IA, Iowa County, IA, Jackson County, IA, Jasper County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Lucas County, IA, Mahaska County, IA, Marion County, IA, Monroe County, IA, Muscatine County, IA, Poweshiek County, IA, Scott County, IA, Tama County, IA, Van Buren County, IA, Wapello County, IA, Warren County, IA, Washington County, IA, Wayne County, IA, Carroll County, IL, Henderson County, IL, Henry County, IL, Mercer County, IL, Rock Island County, IL, Warren County, IL, Whiteside County, IL
The radar
The Des Moines radar (KDMX), 127 km from the middle of the area, began a volume at 16:52 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
28 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 11, 11:57 AM CDT | Tornado Warning | DMX | Clarke, Lucas | 33 min |
| May 11, 12:26 PM CDT | Flash Flood Warning | DMX | Clarke, Decatur, Ringgold, Union | 3 hr |
| May 11, 12:31 PM CDT | Severe Thunderstorm Warning | DMX | Lucas, Wayne | 44 min |
| May 11, 1:09 PM CDT | Tornado Warning | DMX | Lucas, Monroe, Wayne | 36 min |
| May 11, 1:14 PM CDT | Severe Thunderstorm Warning | DMX | Lucas, Mahaska, Marion, Monroe | 61 min |
| May 11, 1:44 PM CDT | Tornado Warning | DMX | Mahaska, Monroe | 31 min |
| May 11, 1:55 PM CDT | Severe Thunderstorm Warning | DMX | Mahaska, Monroe, Wapello | 65 min |
| May 11, 1:59 PM CDT | Tornado Warning | DMX | Mahaska, Wapello | 46 min |
| May 11, 2:24 PM CDT | Severe Thunderstorm Warning | DVN | Jefferson, Keokuk, Washington | 51 min |
| May 11, 2:55 PM CDT | Tornado Warning | DVN | Jefferson, Keokuk | 35 min |
| May 11, 3:11 PM CDT | Severe Thunderstorm Warning | DVN | Lee, Van Buren | 64 min |
| May 11, 3:25 PM CDT | Severe Thunderstorm Warning | DVN | Henry, Jefferson, Keokuk, Washington | 50 min |
| May 11, 3:29 PM CDT | Severe Thunderstorm Warning | DVN | Henry, Mercer, Rock Island | 46 min |
| May 11, 3:32 PM CDT | Tornado Warning | DVN | Henry, Jefferson, Washington | 28 min |
| May 11, 3:33 PM CDT | Severe Thunderstorm Warning | DMX | Wapello | 27 min |
| May 11, 3:36 PM CDT | Severe Thunderstorm Warning | DVN | Jefferson, Van Buren | 39 min |
| May 11, 3:43 PM CDT | Severe Thunderstorm Warning | DVN | Bureau, Henry, Rock Island, Whiteside | 62 min |
| May 11, 3:43 PM CDT | Severe Thunderstorm Warning | DMX | Monroe, Wapello | 62 min |
| May 11, 4:01 PM CDT | Tornado Warning | DMX | Wapello | 44 min |
| May 11, 4:10 PM CDT | Severe Thunderstorm Warning | DVN | Henderson, Mercer, Warren | 50 min |
| May 11, 4:13 PM CDT | Severe Thunderstorm Warning | DVN | Henry, Louisa, Washington | 62 min |
| May 11, 4:14 PM CDT | Severe Thunderstorm Warning | DVN | Des Moines, Henry, Lee | 61 min |
| May 11, 4:18 PM CDT | Severe Thunderstorm Warning | DVN | Henry, Jefferson, Van Buren | 42 min |
| May 11, 4:26 PM CDT | Tornado Warning | DVN | Lee | 34 min |
| May 11, 4:27 PM CDT | Severe Thunderstorm Warning | DMX | Wapello | 33 min |
| May 11, 4:46 PM CDT | Severe Thunderstorm Warning | DVN | Mercer | 59 min |
| May 11, 5:32 PM CDT | Severe Thunderstorm Warning | DVN | Henderson, Mercer, Warren | 58 min |
| May 11, 5:39 PM CDT | Severe Thunderstorm Warning | DVN | Van Buren | 66 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Davenport, (KDVN), launched 12:00Z, 4.9 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
- 52 J/kg
- Mixed-layer CIN
- -261 J/kg
- Mixed-layer LCL
- 1382 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 140 m²/s²
- 0-3 km storm-relative helicity
- 162 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
190 WWUS20 KWNS 111654 SEL1 SPC WW 111654 IAZ000-ILZ000-120000- URGENT - IMMEDIATE BROADCAST REQUESTED TORNADO WATCH NUMBER 141 NWS STORM PREDICTION CENTER NORMAN OK 1155 AM CDT SUN MAY 11 2014 THE NWS STORM PREDICTION CENTER HAS ISSUED A * TORNADO WATCH FOR PORTIONS OF CENTRAL AND EASTERN IOWA NORTHWEST ILLINOIS * EFFECTIVE THIS SUNDAY MORNING AND EVENING FROM 1155 AM UNTIL 700 PM CDT. * PRIMARY THREATS INCLUDE... A COUPLE TORNADOES POSSIBLE ISOLATED VERY LARGE HAIL EVENTS TO 2 INCHES IN DIAMETER POSSIBLE ISOLATED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES WEST OF KNOXVILLE IOWA TO 30 MILES NORTHEAST OF MOLINE ILLINOIS. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1). PRECAUTIONARY/PREPAREDNESS ACTIONS... 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. && DISCUSSION...REMNANTS OF A NOCTURNAL MCS HAVE RECENTLY INTENSIFIED OVER S-CNTRL IA ALONG A WARM FRONT LIFTING NWD THROUGH THE REGION. CONTINUED MOISTENING/DESTABILIZATION AND STRENGTHENING LOW-LEVEL AND DEEP-LAYER SHEAR WILL SUPPORT AN INCREASING THREAT FOR EMBEDDED SUPERCELLS AS STORMS SPREAD NORTHEAST ACROSS THE WATCH AREA. A COUPLE OF TORNADOES...LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE. AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 25030. ...MEAD
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 10, 7:55 PM CDT | Mesoscale Discussion | SPC | Calhoun, Greene, Jersey, Macoupin, Madison, Monroe and 2 more | 95 min |
| May 10, 10:22 PM CDT | Mesoscale Discussion | SPC | Calhoun, Jersey, Madison, Monroe, Randolph, Saint Clair | 83 min |
| May 11, 9:16 AM CDT | Mesoscale Discussion | SPC | Mercer, Rock Island | 89 min |
| May 11, 10:47 AM CDT | Mesoscale Discussion | SPC | Hancock | 118 min |
| May 11, 12:51 PM CDT | Mesoscale Discussion | SPC | Carroll, Henderson, Jo Daviess, Mercer, Rock Island, Whiteside | 54 min |
| May 11, 2:36 PM CDT | Mesoscale Discussion | SPC | Mercer | 84 min |
| May 11, 3:05 PM CDT | Severe Thunderstorm Watch | SPC | Boone, Bureau, Cook, DeKalb, DuPage, Ford and 23 more | 7 hr |
| May 11, 5:09 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Cook, DeKalb, DuPage, Grundy and 21 more | 66 min |
| May 11, 5:49 PM CDT | Mesoscale Discussion | SPC | Clark, Coles, Edgar | 56 min |
| May 11, 1:19 AM CDT | Mesoscale Discussion | SPC | Adams, Cass, Fremont, Harrison, Mills, Montgomery and 3 more | 2 hr |
| May 11, 2:58 AM CDT | Severe Thunderstorm Watch | SPC | Fremont, Mills, Montgomery, Page, Pottawattamie | 7 hr |
| May 11, 7:02 AM CDT | Mesoscale Discussion | SPC | Fremont, Mills, Montgomery, Page, Pottawattamie | 118 min |
| May 11, 12:49 PM CDT | Mesoscale Discussion | SPC | Adams, Cass, Fremont, Mills, Montgomery, Page and 2 more | 116 min |
| May 11, 2:21 PM CDT | Tornado Watch | SPC | Adair, Adams, Audubon, Cass, Fremont, Harrison and 8 more | 8 hr |
| May 11, 6:23 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Cass, Fremont, Mills, Montgomery and 5 more | 67 min |
Nearby
Tornado Watches in Iowa, 2014Tornado Watches in Illinois, 2014Every tornado watch in 2014
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.