Severe Thunderstorm Watch 628

Issued

Sep 7, 2012, 11:36 AM EDT (15:36 UTC)

Expired

Sep 7, 2012, 6:00 PM EDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Northern Indiana radar (KIWX), 127 km from the middle of the area, began a volume at 15:36 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

60%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

30%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

90%

• Mesoscale Discussion 1910Sep 7, 11:09 AM EDT
• Mesoscale Discussion 1911Sep 7, 1:16 PM EDT
• Mesoscale Discussion 1912Sep 7, 2:16 PM EDT
• Mesoscale Discussion 1914Sep 7, 3:39 PM EDT
• Mesoscale Discussion 1917Sep 7, 4:22 PM EDT

106 
WWUS20 KWNS 071537
SEL8
SPC WW 071537
INZ000-OHZ000-072200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 628
NWS STORM PREDICTION CENTER NORMAN OK
1140 AM EDT FRI SEP 7 2012

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

       PARTS OF CENTRAL AND NORTHERN INDIANA
       WEST CENTRAL AND NORTHWEST OHIO

EFFECTIVE THIS FRIDAY MORNING AND EVENING FROM 1140 AM UNTIL 600
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 50
STATUTE MILES NORTH AND SOUTH OF A LINE FROM 45 MILES EAST
SOUTHEAST OF FINDLAY OHIO TO 20 MILES NORTHWEST OF TERRE HAUTE
INDIANA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU8).

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...CONVECTION IS EXPECTED TO INTENSIFY ACROSS NRN INDIANA
ALONG AN OUTFLOW BOUNDARY AND SPREAD EWD INTO W/NW OH THIS
AFTERNOON...WITH ADDITIONAL DEVELOPMENT EXPECTED LATER AND FARTHER
SW ON THE BOUNDARY INTO CENTRAL INDIANA.  GIVEN 0-6 KM BULK SHEAR IN
EXCESS OF 30 KT AND MLCAPE OF 2000-2500 J/KG...ORGANIZED CONVECTIVE
CLUSTERS/LINE SEGMENTS ARE EXPECTED WITH AN ATTENDANT RISK FOR
DAMAGING WINDS AND ISOLATED LARGE HAIL THROUGH THE AFTERNOON.

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 27035.


...THOMPSON

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