

538 

WWUS20 KWNS 181746

SEL1

SPC WW 181746

INZ000-MIZ000-OHZ000-LEZ000-LHZ000-LMZ000-190100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 491

NWS STORM PREDICTION CENTER NORMAN OK

150 PM EDT SUN JUL 18 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       NORTHERN INDIANA

       CENTRAL AND SOUTHERN LOWER MICHIGAN

       NORTHWEST OHIO

       LAKE ERIE

       LAKE HURON

       LAKE MICHIGAN



EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 150 PM UNTIL 900

PM EDT.



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 APPROXIMATELY ALONG AND 65

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

SAGINAW MICHIGAN TO 65 MILES WEST SOUTHWEST OF FORT WAYNE

INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).



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.



DISCUSSION...THUNDERSTORMS ARE INCREASING ALONG A BAND FROM WESTERN

LOWER MI INTO NORTHEASTERN IL.  THESE STORMS ARE LIKELY TO CONTINUE

TO INTENSIFY THIS AFTERNOON AS THE AIR MASS ACROSS MI/IND

DESTABILIZES.  SUFFICIENT FLOW ALOFT WILL ORGANIZE STORMS WITH THE

RISK OF LOCALLY DAMAGING WINDS AND HAIL.



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 500. MEAN STORM

MOTION VECTOR 26030.





...HART

