Tornado Watch 531

Issued

Jun 21, 2011, 1:22 PM CDT (18:22 UTC)

Expired

Jun 21, 2011, 10:00 PM CDT

In force

9 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The St Louis radar (KLSX), 86 km from the middle of the area, began a volume at 18:25 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

40%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

50%

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

70%

• Mesoscale Discussion 1337Jun 21, 11:45 AM CDT
• Mesoscale Discussion 1339Jun 21, 12:56 PM CDT
• Mesoscale Discussion 1341Jun 21, 3:31 PM CDT
• Mesoscale Discussion 1344Jun 21, 4:56 PM CDT
• Mesoscale Discussion 1349Jun 21, 7:20 PM CDT

691 
WWUS20 KWNS 211824
SEL1
SPC WW 211824
ILZ000-KYZ000-MOZ000-220100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 531
NWS STORM PREDICTION CENTER NORMAN OK
125 PM CDT TUE JUN 21 2011

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

       LARGE PART OF CENTRAL AND SOUTHERN ILLINOIS
       PARTS OF WESTERN KENTUCKY
       PARTS OF EASTERN MISSOURI

EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 125 PM UNTIL
800 PM CDT.

TORNADOES...HAIL TO 2 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 80 STATUTE
MILES EAST AND WEST OF A LINE FROM 15 MILES EAST SOUTHEAST OF
POPLAR BLUFF MISSOURI TO 40 MILES NORTHWEST OF CHAMPAIGN
ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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...THE VERY MOIST/MDTLY UNSTABLE AIR MASS ACROSS THE WATCH
HAS BECOME UNCAPPED.  WITH 40KT OF SHEAR COUPLED WITH ENHANCED
ASCENT AHEAD OF MCV MOVING NEWD FROM SRN MO...SEVERE THUNDERSTORMS
INCLUDING SUPERCELLS EXPECTED TO DEVELOP NNEWD JUST AHEAD OF COLD
FRONT ACROSS MO.  PRIMARY THREAT WILL BE LARGE HAIL/WIND
DAMAGE...BUT SHEAR SUPPORTS  TORNADOES WITH ANY SUPERCELL THAT
DEVELOPS.

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
550. MEAN STORM MOTION VECTOR 21035.


...HALES

Tornado Watches in Illinois, 2011Tornado Watches in Missouri, 2011Tornado Watches in Kentucky, 2011Every tornado watch in 2011

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.