

268 

WWUS20 KWNS 062230

SEL0

SPC WW 062230

INZ000-070200-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 260

NWS STORM PREDICTION CENTER NORMAN OK

630 PM EDT SUN MAY 6 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WEST CENTRAL INDIANA



EFFECTIVE THIS SUNDAY EVENING FROM 630 PM UNTIL 1000 PM EDT.



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 25

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 40 MILES SOUTHWEST

OF LAFAYETTE INDIANA TO 25 MILES EAST SOUTHEAST OF LAFAYETTE

INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0).



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 257...WW 258...WW 259...



DISCUSSION...A SMALL CLUSTER OF MERGING STORMS OVER E CENTRAL/NE IL

WILL CONTINUE TO MOVE SEWD ALONG THE INSTABILITY GRADIENT INTO W

CENTRAL INDIANA.  VERTICAL SHEAR IS MARGINAL FOR ORGANIZED SEVERE

STORMS...BUT MLCAPE NEAR 2000 J/KG WILL SUPPORT STRONG UPDRAFTS WITH

THE POTENTIAL FOR AT LEAST ISOLATED LARGE HAIL...WHILE DCAPE IN

EXCESS OF 1000 J/KG WILL SUPPORT A RISK OF DAMAGING DOWNBURSTS.



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 30015.





...THOMPSON

