Severe Thunderstorm Watch for DFW Metroplex

The SPC in Oklahoma has gone ahead and issued a Severe Thunderstorm Watch for our area, expiring at 11pm local time. Today’s threats have changed and has become mainly a hail and wind threat, while the tornado threat is now reduced to near-zero. Severe storms have developed over south central Oklahoma dumping severe-sized hail (larger than 0.75″) along a pre-frontal trough. The cold front is expected to overtake this trough later todayand shift the storm threat from large hail to more of a high wind event. Not sure on exact timing, but previous estimates of 6 to 7pm for ETA around Frisco still seems to hold up. Ill send more updates as I can.

URGENT – IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 752
NWS STORM PREDICTION CENTER NORMAN OK
350 PM CDT THU OCT 1 2009

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

SMALL PART OF SOUTHEAST OKLAHOMA
LARGE PART OF NORTH CENTRAL AND NORTHEAST TEXAS

EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 350 PM UNTIL
1100 PM CDT.

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 85
STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH
NORTHWEST OF PARIS TEXAS TO 20 MILES SOUTH OF TEMPLE TEXAS.  FOR
A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH
OUTLINE UPDATE (WOUS64 KWNS WOU2).

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 751…

DISCUSSION…COLD FRONT MOVING SEWD INTO NRN TX ENCOUNTERING AN AIR
MASS THAT HAS BECOME MDTLY UNSTABLE.  WITH MLCAPES AOA 2000 J/KG AND
DEEP LAYER SHEAR OF 30-40 KT…SEVERE THUNDERSTORMS ARE EXPECTED TO
DEVELOP ALONG AND E OF COLD FRONT AS IT CONTINUES SEWD ACROSS THE
WATCH.

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 550. MEAN STORM
MOTION VECTOR 27025.