Severe Thunderstorm Watch 124

Issued

Mar 31, 2012, 9:24 PM CDT (02:24 UTC)

Expired

Apr 1, 2012, 6:00 AM CDT

In force

9 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Quad Cities radar (KDVN), 23 km from the middle of the area, began a volume at 02:24 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

5%

One or more EF2 to EF5 tornadoes

5%

Ten or more severe wind reports

5%

One or more gusts of 65 knots or more

5%

Ten or more severe hail reports

30%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

50%

• Mesoscale Discussion 402Mar 31, 8:52 PM CDT
• Mesoscale Discussion 404Apr 1, 1:33 AM CDT

636 
WWUS20 KWNS 010224
SEL4
SPC WW 010224
IAZ000-ILZ000-010900-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 124
NWS STORM PREDICTION CENTER NORMAN OK
925 PM CDT SAT MAR 31 2012

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

       EAST CENTRAL IOWA
       NORTHWEST ILLINOIS

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 925 PM
UNTIL 400 AM CDT.

HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 5 MILES SOUTHWEST OF
CEDAR RAPIDS IOWA TO 5 MILES EAST NORTHEAST OF MARSEILLES
ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU4).

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR 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. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY
DO PRODUCE TORNADOES.

OTHER WATCH INFORMATION...CONTINUE...WW 123...

DISCUSSION...AREA OF TSTMS RELATED TO LOW-LEVEL WAA WILL SPREAD
EWD/ESEWD FROM ERN IA INTO NW IL OVERNIGHT.  A FEED OF MUCAPE
APPROACHING 1000 J/KG AND SUBSTANTIAL CLOUD-LAYER VERTICAL SHEAR
WILL SUPPORT ORGANIZED STORMS AND POTENTIALLY AN ELEVATED SUPERCELL
OR TWO...WITH AN ATTENDANT RISK FOR AT LEAST ISOLATED LARGE HAIL.

AVIATION...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 450. MEAN STORM
MOTION VECTOR 29030.


...THOMPSON

Severe Thunderstorm Watches in Illinois, 2012Severe Thunderstorm Watches in Iowa, 2012Every severe thunderstorm 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.