Severe Thunderstorm Watch 569

Issued

Aug 9, 2012, 7:40 PM CDT (00:40 UTC)

Expired

Aug 9, 2012, 11:23 PM CDT

In force

4 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Indianapolis radar (KIND), 109 km from the middle of the area, began a volume at 00:42 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

20%

One or more EF2 to EF5 tornadoes

5%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

10%

Ten or more severe hail reports

50%

One or more hailstones of 2 inches or more

10%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 1730Aug 9, 7:10 PM CDT

892 
WWUS20 KWNS 100043
SEL9
SPC WW 100043
ILZ000-INZ000-100700-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 569
NWS STORM PREDICTION CENTER NORMAN OK
740 PM CDT THU AUG 9 2012

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

       CENTRAL AND EASTERN ILLINOIS
       CENTRAL AND SOUTHERN INDIANA

EFFECTIVE THIS THURSDAY NIGHT AND FRIDAY MORNING FROM 740 PM
UNTIL 200 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 70
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 10 MILES NORTHWEST
OF DECATUR ILLINOIS TO 35 MILES SOUTH SOUTHEAST OF MUNCIE
INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).

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...THIS SEVERE THUNDERSTORM WATCH REPLACES
SEVERE THUNDERSTORM WATCH NUMBER 568. WATCH NUMBER 568 WILL NOT
BE IN EFFECT AFTER 740 PM CDT. CONTINUE...WW 567...

DISCUSSION...SCTD AREAS OF TSTMS EXPECTED TO CONTINUE FORMING
THROUGH AT LEAST LATE EVE IN WW AREA...IN ZONE OF INCREASING MID LVL
COOLING AND ASCENT DOWNSTREAM FROM SHORTWAVE TROUGH NOW AMPLIFYING
SEWD FROM ERN IA.  AMPLE DEEP SHEAR WILL BE PRESENT FOR SUSTAINED
STORMS AND POSSIBLY SPLITTING SUPERCELLS WITH SVR HAIL/WIND.  AN
ISOLD TORNADO CANNOT BE RULED OUT...ESPECIALLY ALONG STALLING W-E
OUTFLOW IN N CNTRL IND...BUT ANY SUCH THREAT SHOULD BE SHORT-LIVED.

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 500. MEAN STORM
MOTION VECTOR 30025.


...CORFIDI

Severe Thunderstorm Watches in Indiana, 2012Severe Thunderstorm Watches in Illinois, 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.