

149 

WWUS20 KWNS 102030

SEL2

SPC WW 102030

ILZ000-INZ000-MOZ000-110100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 502

NWS STORM PREDICTION CENTER NORMAN OK

325 PM CDT WED SEP 10 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  CENTRAL...EASTERN...AND SOUTHERN ILLINOIS

  NORTHWEST INDIANA

  EAST CENTRAL AND SOUTHEAST MISSOURI



* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 325 PM

  UNTIL 800 PM CDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  ISOLATED LARGE HAIL EVENTS TO 1 INCH IN DIAMETER POSSIBLE

  A TORNADO OR TWO POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 85

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF

LAFAYETTE INDIANA TO 45 MILES SOUTH SOUTHWEST OF SCOTT AFB

ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 501...



DISCUSSION...TSTMS EXPECTED TO CONTINUE SLOWLY INCREASE ALONG

CONFLUENCE BANDS AHEAD OF SE-MOVING CNTRL MO/NRN IL COLD FRONT

THROUGH LATER TNGT. DEVELOPMENT WILL BE FOSTERED BY ASCENT/WEAK

MID-LVL COLD ADVECTION ON SRN FRINGE OF ERN IA UPR IMPULSE...SFC

HEATING...AND CONTINUED MOISTURE INFLOW. WHILE WSWLY DEEP SHEAR

SHOULD WEAKEN WITH TIME AS STRONGER LEAD UPR IMPULSE CONTINUES NE

ACROSS LK ERIE...AMPLE SHEAR SHOULD REMAIN FOR SUSTAINED

STORMS/POSSIBLE SUPERCELLS GIVEN EXPECTED THERMODYNAMIC ENVIRONMENT

AND AT LEAST MODEST LOW-LVL CONVERGENCE. WHILE THE MAIN SVR THREAT

SHOULD BE LOCALLY DMGG WIND...A TORNADO OR TWO CANNOT BE RULED

OUT...ESPECIALLY IN CNTRL/ERN IL AND PERHAPS ADJACENT SE MO.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION

VECTOR 26035.





...CORFIDI



458 

WWUS20 KWNS 102030

SEL2

SPC WW 102030

ILZ000-INZ000-MOZ000-110100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 502

NWS STORM PREDICTION CENTER NORMAN OK

325 PM CDT WED SEP 10 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  CENTRAL...EASTERN...AND SOUTHERN ILLINOIS

  NORTHWEST INDIANA

  EAST CENTRAL AND SOUTHEAST MISSOURI



* EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 325 PM

  UNTIL 800 PM CDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH POSSIBLE

  ISOLATED LARGE HAIL EVENTS TO 1 INCH IN DIAMETER POSSIBLE

  A TORNADO OR TWO POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 85

STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF

LAFAYETTE INDIANA TO 45 MILES SOUTH SOUTHWEST OF SCOTT AFB

ILLINOIS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 501...



DISCUSSION...TSTMS EXPECTED TO CONTINUE SLOWLY INCREASE ALONG

CONFLUENCE BANDS AHEAD OF SE-MOVING CNTRL MO/NRN IL COLD FRONT

THROUGH LATER TNGT. DEVELOPMENT WILL BE FOSTERED BY ASCENT/WEAK

MID-LVL COLD ADVECTION ON SRN FRINGE OF ERN IA UPR IMPULSE...SFC

HEATING...AND CONTINUED MOISTURE INFLOW. WHILE WSWLY DEEP SHEAR

SHOULD WEAKEN WITH TIME AS STRONGER LEAD UPR IMPULSE CONTINUES NE

ACROSS LK ERIE...AMPLE SHEAR SHOULD REMAIN FOR SUSTAINED

STORMS/POSSIBLE SUPERCELLS GIVEN EXPECTED THERMODYNAMIC ENVIRONMENT

AND AT LEAST MODEST LOW-LVL CONVERGENCE. WHILE THE MAIN SVR THREAT

SHOULD BE LOCALLY DMGG WIND...A TORNADO OR TWO CANNOT BE RULED

OUT...ESPECIALLY IN CNTRL/ERN IL AND PERHAPS ADJACENT SE MO.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1 INCH. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS.

A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. MEAN STORM MOTION

VECTOR 26035.





...CORFIDI

