

126 

WWUS20 KWNS 051907

SEL5

SPC WW 051907

ILZ000-INZ000-MIZ000-OHZ000-LEZ000-LHZ000-LMZ000-060100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 495

NWS STORM PREDICTION CENTER NORMAN OK

305 PM EDT FRI SEP 5 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN ILLINOIS

  NORTHERN INDIANA

  SOUTHERN AND EASTERN LOWER MICHIGAN

  NORTHWEST OHIO

  LAKE ERIE

  LAKE HURON

  LAKE MICHIGAN



* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 305 PM UNTIL

  900 PM EDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH LIKELY

  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 15 MILES EAST

SOUTHEAST OF MOUNT CLEMENS MICHIGAN TO 65 MILES WEST OF

VALPARAISO INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



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.



&&



DISCUSSION...TSTMS EXPECTED TO INCREASE IN COVERAGE/STRENGTH ALONG

AND AHEAD OF ESE-MOVING COLD FRONT NOW APPROACHING THE WRN SUBURBS

OF CHICAGO AND WRN LWR MI. DEVELOPMENT ALSO MAY OCCUR ALONG

PRE-FRONTAL CONFLUENCE AXES AND LAKE BREEZE BOUNDARIES IN NRN IN/SRN

MI. BAND OF ELEVATED STORMS NOW FORMING E OF ROCKFORD IL MAY

INTENSIFY AS IT OUTPACES SFC COLD FRONT AND ENCOUNTERS GREATER

LOW-LVL INSTABILITY IN THE CHICAGO AREA OVER THE NEXT 1-2 HRS. THESE

STORMS...AND THOSE FORMING FARTHER E...WILL HAVE A TENDENCY TO

ORGANIZE INTO N-S LINES. ASSOCIATED EMBEDDED BOWS WILL POSE A RISK

FOR DMGG WIND AND POSSIBLY SVR HAIL THOUGH EARLY TNGT GIVEN VERY

WARM/MOIST LOW-LVL ENVIRONMENT...RESIDUAL EML...AND 35+ KT WSWLY

UNIDIRECTIONAL 700-500 MB FLOW.



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 550. MEAN STORM

MOTION VECTOR 26035.





...CORFIDI



735 

WWUS20 KWNS 051907

SEL5

SPC WW 051907

ILZ000-INZ000-MIZ000-OHZ000-LEZ000-LHZ000-LMZ000-060100-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 495

NWS STORM PREDICTION CENTER NORMAN OK

305 PM EDT FRI SEP 5 2014



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN ILLINOIS

  NORTHERN INDIANA

  SOUTHERN AND EASTERN LOWER MICHIGAN

  NORTHWEST OHIO

  LAKE ERIE

  LAKE HURON

  LAKE MICHIGAN



* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 305 PM UNTIL

  900 PM EDT.



* PRIMARY THREATS INCLUDE...

  SCATTERED DAMAGING WIND GUSTS TO 70 MPH LIKELY

  ISOLATED LARGE HAIL EVENTS TO 1.5 INCHES IN DIAMETER POSSIBLE



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 75

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 15 MILES EAST

SOUTHEAST OF MOUNT CLEMENS MICHIGAN TO 65 MILES WEST OF

VALPARAISO INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



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.



&&



DISCUSSION...TSTMS EXPECTED TO INCREASE IN COVERAGE/STRENGTH ALONG

AND AHEAD OF ESE-MOVING COLD FRONT NOW APPROACHING THE WRN SUBURBS

OF CHICAGO AND WRN LWR MI. DEVELOPMENT ALSO MAY OCCUR ALONG

PRE-FRONTAL CONFLUENCE AXES AND LAKE BREEZE BOUNDARIES IN NRN IN/SRN

MI. BAND OF ELEVATED STORMS NOW FORMING E OF ROCKFORD IL MAY

INTENSIFY AS IT OUTPACES SFC COLD FRONT AND ENCOUNTERS GREATER

LOW-LVL INSTABILITY IN THE CHICAGO AREA OVER THE NEXT 1-2 HRS. THESE

STORMS...AND THOSE FORMING FARTHER E...WILL HAVE A TENDENCY TO

ORGANIZE INTO N-S LINES. ASSOCIATED EMBEDDED BOWS WILL POSE A RISK

FOR DMGG WIND AND POSSIBLY SVR HAIL THOUGH EARLY TNGT GIVEN VERY

WARM/MOIST LOW-LVL ENVIRONMENT...RESIDUAL EML...AND 35+ KT WSWLY

UNIDIRECTIONAL 700-500 MB FLOW.



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 550. MEAN STORM

MOTION VECTOR 26035.





...CORFIDI

