Strong Wind in Texas, November 15, 2005

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE FORT WORTH TX
605 AM CST TUE NOV 15 2005

.AVIATION..
FRONT AHEAD OF SCHEDULE WITH INTENSE 3 HOUR PRESSURE RISES OF 9 MB
OCCURRING ALL NIGHT ACROSS THE TX PANHANDLE.  GRAVITY WAVE WHICH
ORIGINATED IN SE COLORADO APPEARED ON WATER VAPOR LOOP SEVERAL HOURS
AGO AND COINCIDES WITH A PRE-FRONTAL TROUGH AND RADAR FINE LINES.
WESTERLY WIND SHIFT WILL BE FIRST...WITH THE FRONT AN HOUR LATER.
WIND SHIFT TIMING BASED ON EXTRAPOLATION...WITH MAIN FROPA 13-14Z IN
THE METROPLEX AND 16Z FOR KACT.  BEHIND THE FRONT GUSTS TO 35 KT
POSSIBLE FOR METROPLEX SITES TODAY.  DID NOT SHOW GUSTS THAT HIGH IN
TAFS SINCE THE OCCURRENCE WILL BE A ONE TIME OR INFREQUENT
EVENT...BUT WILL NEED TO ISSUE AN AIRPORT WEATHER WARNING IN AN HOUR
OR SO.  PREVAILING WINDS OF 33023G32 KT SHOULD COVER THINGS TODAY.
WINDS WILL SUBSIDE LATE THIS AFTERNOON AND INTO TONIGHT.

WINDS ABOVE THE SURFACE ARE BECOMING MORE WESTERLY NOW AND IT IS
ADVECTING THE MVFR STRATUS EASTWARD. THEREFORE EXPECT VFR FOR
METROPLEX SITES TO PREVAIL THROUGH THE PERIOD...BUT HELD A TEMPO
MVFR FOR KACT THRU 14Z FOR LINGERING STRATUS THERE.  0Z-6Z SOUNDING
INDICATING SUBSIDENCE AND A MORE STABLE BOUNDARY LAYER AND BELIEVE
THIN LINE OF CONVECTION WILL DEVELOP ALONG THE FRONT E OF TAF SITES.

TR/92

&&

.DISCUSSION...
A VERY DYNAMIC WEATHER PATTERN CONTINUES TO EVOLVE ACROSS THE
CENTRAL CONUS THIS MORNING...COURTESY OF A POWERFUL UPPER LOW
DEEPENING OVER THE NORTHERN PLAINS.  THE SURFACE COLD FRONT
ACCOMPANYING THIS FEATURE WAS LOCATED FROM CENTRAL OKLAHOMA...
SOUTHWESTWARD TO THE SOUTHERN TEXAS PANHANDLE AS OF 10Z.  SUSTAINED
WINDS IN THE 25-35 MPH RANGE...WITH GUSTS IN THE 35-45 MPH RANGE
HAVE BEEN REPORTED FOR MUCH OF THE NIGHT IN THE POSTFRONTAL
AIRMASS...AND EXPECT THIS TREND TO CONTINUE AS THE FRONT SURGES
ACROSS NORTH TEXAS LATER THIS MORNING.  SHORT TERM NAM/GFS GUIDANCE
IS IN CLOSE AGREEMENT ON FRONT ENTERING THE NORTHWEST PORTION OF THE
FORECAST AREA AROUND 12Z...AND QUICKLY SWEEPING ACROSS THE AREA WITH
ONLY THE FAR SOUTHEASTERN COUNTIES REMAINING IN THE WARM SECTOR BY
18Z.

MODEL GUIDANCE CONTINUES TO ADVERTISE A NARROW/BROKEN LINE OF
CONVECTION DEVELOPING IMMEDIATELY AHEAD OF THE COLD FRONT...AS IT
INTERCEPTS PROGRESSIVELY DEEPER MOISTURE TO THE EAST OF THE I-35
CORRIDOR.  THUS...WE WILL MAINTAIN CHANCE POPS ACROSS THE EASTERN
HALF OF THE AREA...AND PLACE HIGHEST POPS ACROSS THE NORTHEAST WHERE
CONVERGENCE AND LIFT WILL BE MAXIMIZED BENEATH THE RIGHT ENTRANCE
REGION OF A 90-110 KNOT UPPER SPEED MAX.  A NARROW BAND OF
CONVECTION WILL LIKELY DEVELOP SOUTHWESTWARD ALONG THE COLD FRONT
THROUGH THE AFTERNOON...BUT BY THIS TIME THE BOUNDARY SHOULD BE EAST
OF OUR FORECAST AREA.  ONCE AGAIN...UNFAVORABLE FRONTAL TIMING WILL
LIKELY PRECLUDE A WIDESPREAD SEVERE WEATHER EVENT ACROSS NORTH
TEXAS.  HOWEVER...INCREASING DEEP LAYER SHEAR AND INSTABILITY WILL
SUPPORT SOME STRONG STORMS PRODUCING GUSTY WINDS AND SMALL HAIL.

MEANWHILE...STRONG BOUNDARY LAYER MIXING AND DOWNWARD TRANSPORT OF
HORIZONTAL MOMENTUM WILL AUGMENT ISALLOBARIC FORCING TO LEAD TO VERY
WINDY CONDITIONS ACROSS THE NORTHWEST HALF OF NORTH TEXAS THIS
AFTERNOON.  WE HAVE MAINTAINED THE WIND ADVISORY...AND ANTICIPATE
GUSTS IN THE 35-45 MPH RANGE.  THE HIGH WINDS...ALONG WITH STRONG
NEGATIVE MOISTURE ADVECTION WILL RESULT IN DANGEROUS FIRE WEATHER
CONDITIONS ACROSS THE SAME REGION...AND HAVE ALSO MAINTAINED THE RED
FLAG WARNING INHERITED FROM THE PREVIOUS PACKAGE.  FINALLY...DESPITE
WINDS REMAINING LIGHT OVERNIGHT...CLEAR SKIES AND VERY LOW DEWPOINTS
WILL LIKELY RESULT IN A SIGNIFICANT FREEZE ACROSS GENERALLY THE
NORTHWEST HALF OF THE AREA BY WEDNESDAY MORNING.  A FREEZE WARNING
HAS BEEN ISSUED TO HIGHLIGHT THIS THREAT.

OTHERWISE...A RETURN TO TRANQUIL WEATHER WILL OCCUR FOR THE
REMAINDER OF THIS FORECAST PERIOD.  MEDIUM RANGE ECMWF/GFSLR
GUIDANCE CONTINUES TO INDICATE PERSISTENT TROUGHING ACROSS THE
GREAT LAKES AND UPPER MIDWEST...WITH AN UPPER RIDGE PROGGED TO
AMPLIFY OVER THE WESTERN U.S.  THUS...SEVERAL COLD FRONTAL PASSAGE
ARE ANTICIPATED OVER THE UPCOMING WEEK...BUT WITH THE AIRMASS ACROSS
NORTH TEXAS REMAINING TOO DRY AND STABLE TO SUPPORT CONVECTION.

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  73  32  59  33 /  20   0   0   0
WACO, TX              76  34  61  31 /  20   0   0   0
PARIS, TX             77  32  54  33 /  50   0   0   0
DENTON, TX            71  31  57  34 /  20   0   0   0
MCKINNEY, TX          74  32  55  33 /  40   0   0   0
DALLAS, TX            74  33  59  33 /  30   0   0   0
TERRELL, TX           78  34  58  32 /  40   0   0   0
CORSICANA, TX         79  35  60  31 /  30   0   0   0
TEMPLE, TX            78  34  62  31 /  20   0   0   0

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 6 PM TUESDAY FOR TXZ091-TXZ092-TXZ093-TXZ094-
TXZ095-TXZ100-TXZ101-TXZ102-TXZ103-TXZ104-TXZ105-TXZ106-TXZ107-
TXZ115-TXZ116-TXZ117-TXZ118-TXZ119-TXZ120-TXZ121-TXZ122-TXZ123-
TXZ129-TXZ130-TXZ131-TXZ132-TXZ133-TXZ134-TXZ135-TXZ141-TXZ142-
TXZ143-TXZ144-TXZ145-TXZ146-TXZ156-TXZ157-TXZ158-TXZ159.

RED FLAG WARNING FROM 11 AM TUESDAY TO 6 PM TUESDAY FOR TXZ091-
TXZ092-TXZ093-TXZ094-TXZ100-TXZ101-TXZ102-TXZ103-TXZ104-TXZ115-
TXZ116-TXZ117-TXZ118-TXZ119-TXZ129-TXZ130-TXZ131-TXZ132-TXZ133-
TXZ141-TXZ142-TXZ143-TXZ144-TXZ156-TXZ157.

FREEZE WARNING FROM 3 AM WEDNESDAY TO 8 AM WEDNESDAY FOR TXZ091-
TXZ092-TXZ093-TXZ094-TXZ095-TXZ100-TXZ101-TXZ102-TXZ103-TXZ104-
TXZ105-TXZ106-TXZ115-TXZ116-TXZ117-TXZ118-TXZ129-TXZ130-TXZ131-
TXZ132-TXZ133-TXZ141-TXZ142-TXZ143-TXZ144-TXZ156-TXZ157.

&&

65/DD

HAZARDOUS WEATHER OUTLOOK FOR NORTH TEXAS
NATIONAL WEATHER SERVICE FORT WORTH TX
400 AM CST TUE NOV 15 2005

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-152200-
ANDERSON-BELL-BOSQUE-COLLIN-COMANCHE-COOKE-CORYELL-DALLAS-DELTA-
DENTON-EASTLAND-ELLIS-ERATH-FALLS-FANNIN-FREESTONE-GRAYSON-HAMILTON-
HENDERSON-HILL-HOOD-HOPKINS-HUNT-JACK-JOHNSON-KAUFMAN-LAMAR-LAMPASAS-
LEON-LIMESTONE-MCLENNAN-MILAM-MILLS-MONTAGUE-NAVARRO-PALO PINTO-
PARKER-RAINS-ROBERTSON-ROCKWALL-SOMERVELL-STEPHENS-TARRANT-VAN ZANDT-
WISE-YOUNG-
400 AM CST TUE NOV 15 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...
A STRONG COLD FRONT WILL MOVE THROUGH NORTH TEXAS THIS MORNING AND
BRING A CHANCE OF THUNDERSTORMS TO LOCATIONS MAINLY ALONG AND EAST
OF THE INTERSTATE 35 CORRIDOR.  SOME STORMS MAY BECOME STRONG EAST
OF A LINE FROM BONHAM...TO CORSICANA...TO HEARNE...AND PRODUCE WIND
GUSTS OVER 50 MPH AND SMALL HAIL.

BEHIND THE FRONT...GUSTY NORTHERLY WINDS AND COLDER TEMPERATURES ARE
EXPECTED.  SUSTAINED WINDS WILL INCREASE TO 20 TO 30 MPH.  WINDS
WILL BE STRONGEST FOR THE AREA THAT IS NORTH OF I-20 AND WEST OF
I-35 WHERE WINDS WILL GUST TO 40 MPH.  A WIND ADVISORY IS IN EFFECT
FOR ALL OF NORTH TEXAS...EXCEPT FOR THE AREA ALONG AND SOUTHEAST OF
A LINE FROM PALESTINE...TO MARLIN...TO CAMERON.

THE STRONG WINDS WILL ALSO COMBINE WITH LOW RELATIVE HUMIDITY VALUES
THIS AFTERNOON TO PRODUCE A DANGEROUS FIRE WEATHER THREAT.
THEREFORE A RED FLAG WARNING IS IN EFFECT FOR THE AREA ALONG AND
WEST OF A LINE FROM BONHAM...TO DALLAS...TO CLEBURNE...TO
GATESVILLE.

LASTLY...THE FIRST WIDESPREAD FREEZE OF THE SEASON IS EXPECTED
TONIGHT ALONG AND NORTHWEST OF A LINE FROM COOPER...TO
GREENVILLE...TO PLANO...TO ARLINGTON...TO GATESVILLE...WHERE A
FREEZE WARNING HAS BEEN ISSUED.

.DAYS TWO THROUGH SEVEN...
A DRY AND STABLE AIRMASS WILL BE OVER NORTH TEXAS THROUGH
MONDAY...AND THEREFORE HAZARDOUS WEATHER IS NOT EXPECTED.

.SPOTTER INFORMATION STATEMENT...
VERY LIMITED SPOTTER ACTIVATION MAY BE REQUESTED EAST OF A BONHAM TO
HEARNE LINE LATE THIS MORNING AND EARLY THIS AFTERNOON.

92