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venture
10-29-2009, 02:01 AM
http://www.spc.noaa.gov/products/watch/ww0779_radar.gif

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 779
NWS STORM PREDICTION CENTER NORMAN OK
200 AM CDT THU OCT 29 2009

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

CENTRAL AND SOUTHWESTERN OKLAHOMA
NORTHWESTERN TEXAS

EFFECTIVE THIS THURSDAY MORNING FROM 200 AM UNTIL 900 AM CDT.

SEVERAL TORNADOES
WIDELY SCATTERED DAMAGING WINDS
ISOLATED WIND GUSTS TO 70 MPH POSSIBLE
WIDELY SCATTERED LARGE HAIL TO 1.0 INCH IN DIAMETER

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 60 STATUTE
MILES EAST AND WEST OF A LINE FROM 25 MILES SOUTH SOUTHEAST OF
ABILENE TEXAS TO 40 MILES NORTH OF OKLAHOMA CITY OKLAHOMA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU9).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND 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.

OTHER WATCH INFORMATION...CONTINUE...WW 778...

DISCUSSION...A LINE OF STORMS FROM WEST CENTRAL OK SWWD INTO NWRN TX
WAS SLOWLY BECOMING BETTER ORGANIZED...AS STRONGER FORCING SPREADS
IN FROM THE SOUTHWEST. STRONGER CONVECTION CURRENTLY IS LOCATED
ALONG OR JUST BEHIND COLD FRONT. AS THE LINE MOVES SLOWLY EWD INTO A
MODERATELY UNSTABLE AIR MASS AND DEWPOINTS IN THE MID 60S...THE
POTENTIAL FOR SURFACE BASED STORMS WILL INCREASE. ALSO...GIVEN
EFFECTIVE SHEAR AT 60-70 KT AND 1 KM SRH IN THE 400-500 M2/S2
RANGE...ROTATING STORMS ARE LIKELY WITH EMBEDDED BOWS/WIND DAMAGE
AND POSSIBLY TORNADOES.

AVIATION...TORNADOES AND 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 500.
MEAN STORM MOTION VECTOR 21040.

New Tornado Watch including the rest of the Metro.

WW 779 TORNADO OK TX 290700Z - 291400Z
AXIS..60 STATUTE MILES EAST AND WEST OF LINE..
25SSE ABI/ABILENE TX/ - 40N OKC/OKLAHOMA CITY OK/ ..AVIATION COORDS.. 50NM E/W /29SE ABI - 27SE END/ HAIL SURFACE AND ALOFT..1 INCH. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 21040.

Thunder
10-29-2009, 02:49 AM
I hope Karrie is sleeping.

venture
10-29-2009, 04:01 AM
http://www.spc.noaa.gov/products/md/mcd2152.gif

MESOSCALE DISCUSSION 2152
NWS STORM PREDICTION CENTER NORMAN OK
0340 AM CDT THU OCT 29 2009

AREAS AFFECTED...PARTS OF CNTRL/SRN OK INTO NRN TX

CONCERNING...TORNADO WATCH 778...779...

VALID 290840Z - 291015Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 778...779...CONTINUES.

THE THREAT FOR DAMAGING WIND GUSTS AND TORNADOES CONTINUES ACROSS WW
AREAS.

EXCEPT FOR A SMALL CLUSTER OF DEEP SHOWERS/TSTMS OVER BRYAN COUNTY
OK...MOIST CONVECTION HAS DIMINISHED ACROSS WW 778 AREA. BASED ON
2-HR PRESSURE TENDENCIES...IT IS POSSIBLE THAT THE STRONGEST
LOW-LEVEL FORCING FOR ASCENT /I.E. WAA/ IS SHIFTING NNEWD TOWARD THE
OZARK PLATEAU. HOWEVER...RADAR DATA DO CONTINUE TO INDICATE WEAK
SHOWERS PRESENT FROM THE HILL COUNTRY NWD THROUGH N-CNTRL
TX...INDICATIVE OF BROAD WAA OCCURRING ALONG 50-60 KT LLJ. AS
SUCH...THE POTENTIAL EXISTS FOR STORM REGENERATION...PARTICULARLY AS
LINEAR SYSTEM APPROACHES FROM THE W. KINEMATIC ENVIRONMENT WILL
REMAIN QUITE FAVORABLE FOR SUPERCELLS CAPABLE OF TORNADOES.

FARTHER W ACROSS WW779...BROKEN CONVECTIVE BAND WHICH EARLIER
INTENSIFIED...NOW APPEARS TO BE STRUGGLING WITH ANAFRONTAL AIRFLOW
REGIME. THIS IS LIKELY BEGIN EXACERBATED BY CONVECTIVE OUTFLOW
GENERATED BY ONGOING STORMS. AS OF 0820Z...THE STRONGEST STORMS
WERE LOCATED OVER WA****A AND KIOWA COUNTIES AND FARTHER S OVER
WILBARGER AND BAYLOR COUNTIES IN NW TX. THE WILBARGER/BAYLOR COUNTY
COMPLEX HAS EXHIBITED BOWING PROPERTIES WHILE FORWARD-PROPAGATING
NEWD AT AROUND 45 KT.

BASED ON CURRENT RADAR TRENDS...IT APPEARS THAT THE REGION BOUNDED
BY I-40...U.S. 287 AND I-35 WILL BE THE MOST LIKELY AREA FOR
ISOLATED SEVERE WEATHER THROUGH 10-11Z. HERE...THE STRONGER
SYNOPTIC-FORCING FOR ASCENT ATTENDANT TO MID/UPPER JET STREAK
LIFTING NWD THROUGH THE HIGH PLAINS WILL REMAIN COINCIDENT WITH
MOISTENING/DESTABILIZING PRE-FRONTAL WARM SECTOR.