Severe Thunderstorm Watch 521

Issued

Jul 22, 2002, 2:30 PM CDT (19:30 UTC)

Expired

Jul 22, 2002, 8:00 PM CDT

In force

6 hr

Issued by

the Storm Prediction Center

The Lincoln radar (KILX), 81 km from the middle of the area, began a volume at 19:29 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.

000 
WWUS20 KWNS 221933
SEL1  
SPC WW 221930
ILZ000-INZ000-MIZ000-230100-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 521
STORM PREDICTION CENTER NORMAN OK
230 PM CDT MON JUL 22 2002

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

   NORTHERN AND CENTRAL ILLINOIS                           
   NORTHWESTERN INDIANA                            
   EXTREME SOUTHWEST LOWER MICHIGAN                           

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 230 PM UNTIL 800
PM CDT.

HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70
MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 60 STATUTE MILES
NORTH AND SOUTH OF A LINE FROM 40 MILES WEST NORTHWEST OF
SPRINGFIELD ILLINOIS TO 55 MILES SOUTH SOUTHEAST OF SOUTH BEND
INDIANA.

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 520...

DISCUSSION...DEEP CONVERGENCE ASSOCIATED WITH COLD FRONT EXTENDS
FROM SWRN LOWER MI SWWD ACROSS THE SRN PORTIONS OF THE CHICAGO AREA
INTO NORTHERN MO.  AIR MASS IS EXTREMELY UNSTABLE AHEAD OF THIS
FRONT...AND FRONT SHOULD INITIATE SEVERE THUNDERSTORMS AS IT MOVES
SOUTHEASTWARD THROUGH THE EVENING.  THOUGH SHEAR IS MARGINAL...
LINEAR FORCING ASSOCIATED WITH FRONT AND EXTREME INSTABILITY WILL
INCREASE THE THREAT OF WIND DAMAGE WITH THESE STORMS.


AVIATION...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 26035.


...EVANS

405,0902 414,0855 400,0855 391,0902

Severe Thunderstorm Watches in Illinois, 2002Severe Thunderstorm Watches in Indiana, 2002Every severe thunderstorm watch in 2002

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.