Tornado Watch 234

Issued

May 3, 2012, 7:09 PM CDT (00:09 UTC)

Expired

May 4, 2012, 1:00 AM CDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

3 in

Strongest gust expected

60 kt

The Des Moines radar (KDMX), 126 km from the middle of the area, began a volume at 00:12 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.

Two or more tornadoes

30%

One or more EF2 to EF5 tornadoes

10%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

40%

Ten or more severe hail reports

70%

One or more hailstones of 2 inches or more

70%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 679May 3, 3:41 PM CDT
• Mesoscale Discussion 680May 3, 3:53 PM CDT
• Mesoscale Discussion 685May 3, 6:42 PM CDT
• Mesoscale Discussion 688May 3, 11:18 PM CDT

430 
WWUS20 KWNS 040011
SEL4
SPC WW 040011
IAZ000-ILZ000-KSZ000-MOZ000-040600-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 234
NWS STORM PREDICTION CENTER NORMAN OK
710 PM CDT THU MAY 3 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       SOUTHERN IOWA
       EXTREME WEST CENTRAL ILLINOIS
       EXTREME NORTHEAST KANSAS
       NORTHERN MISSOURI

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 710 PM
UNTIL 100 AM CDT.

TORNADOES...HAIL TO 3 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 65 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 50 MILES NORTH NORTHWEST OF
SAINT JOSEPH MISSOURI TO 35 MILES SOUTHEAST OF BURLINGTON IOWA.
FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU4).

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 231...WW 232...WW 233...

DISCUSSION...THUNDERSTORMS ARE EXPECTED TO INCREASE IN
COVERAGE/INTENSITY THIS EVENING THROUGH EARLY TONIGHT ACROSS NRN
MO/SRN IA AS LOW-LEVEL WAA INCREASES ALONG A DIFFUSE/REMNANT OUTFLOW
BOUNDARY THAT IS DRIFTING NWD INTO IA.  00Z TOP SOUNDING IS
REPRESENTATIVE OF THE STRONG INSTABILITY PRESENT ACROSS THE SRN/WRN
PORTIONS OF THE WATCH AREA...AND VERTICAL SHEAR IS AT LEAST
MARGINALLY FAVORABLE FOR SUPERCELLS WITH SOME RISK FOR A TORNADO OR
TWO.  OTHERWISE...VERY LARGE HAIL WILL BE POSSIBLE WITH THE MORE
DISCRETE STORMS IN THE NEXT FEW HOURS...WHILE THE RISK FOR DAMAGING
WINDS WILL INCREASE AS STORMS MERGE AND GROW UPSCALE INTO
BANDS/CLUSTERS TONIGHT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
550. MEAN STORM MOTION VECTOR 27025.


...THOMPSON

Tornado Watches in Missouri, 2012Tornado Watches in Iowa, 2012Tornado Watches in Illinois, 2012Every tornado watch in 2012

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.