FXUS64 KFWD 061751 AAC
AFDFWD

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
1251 PM CDT MON OCT 6 2008

.AVIATION...
DIFFICULT TO PINPOINT TIMING OF FINAL ROUND OF TSRA POSSIBILITIES
ACROSS N TX AIRPORTS...BUT FOR NOW PER LATEST ST MODEL PROGS...WILL
ONLY HAVE VCTS/CB GROUP BETWEEN 20Z AND 00Z...WITH SOME LINGER VFR
DECKS/SHRA AROUND BTWN 00Z-09Z TUES A.M...AS BASE OF MAIN UPR ENERGY
LIFTS TO OUR N ACROSS OK/SRN KS. THIS WILL DRAG PRE-FRONTAL TROF ACROSS
AREA BTWN 06Z-09Z WITH SW-W WNDS BLO 10 KTS.

REAL FROPA/CAA ARRIVES BY 12Z/AFTR WITH ENOUGH CAA FOR SOME GSTY
NW WNDS 15-20 MPH...WITH SOME GSTS IN EXCESS OF 25 MPH. PER BL MSTR
PROGS/SOUNDINGS/AND GUIDANCE...IT APPEARS WRAP-AROUND /POST-FRONTAL
MVFR CIGS TO REMAIN FROM RED RIVER VALLEY/NWD WHERE MORE INTENSE CAA
TO OCCUR. THIS WILL NEED TO BE MONITORED BY LATER FCSTS CLOSELY.


05/

&&

.UPDATE...
WILL UPDATE PACKAGE TO LOWER THUNDER TO ISOLD THIS MORNING RATHER
THAN PREDOMINANT. OTHERWISE...12Z NAM VERY SIMILAR TO EARLIER RUN
AND WILL KEEP REST OF PACKAGE SAME. 84

&&

.PREV DISCUSSION... /ISSUED 425 AM CDT MON OCT 6 2008/
A CLOSED UPPER LEVEL LOW AT THE BASE OF A LONGWAVE TROUGH IS NOW
PUSHING THROUGH THE TX PANHANDLE...WITH A LINE OF STORMS ALONG
AND AHEAD OF THIS FEATURE MOVING THROUGH NORTH TEXAS. STORMS ARE
PRIMARILY ELEVATED IN NATURE...AND LACK OF SURFACE COLD POOL AND
ESSENTIALLY UNIDIRECTIONAL S/SW UPPER FLOW MEANS SLOW/STEADY
EASTWARD MOTION WILL CONTINUE THROUGH THE NEXT FEW HOURS.
DISSIPATING LOW LEVEL JET AND DIMINISHING UPPER LEVEL DYNAMIC
SUPPORT AS THE UPPER LOW VEERS OFF TO THE NORTH INTO THE CENTRAL
PLAINS MEANS STORMS WILL GRADUALLY WEAKEN IN INTENSITY THIS
MORNING. POP FORECAST WILL SHOW CATEGORICAL RAIN CHANCES OVER THE
CENTRAL ZONES WITH LIKELY RAIN EAST...HOWEVER QPF WILL TAPER OFF
FROM WEST TO EAST DUE TO EXPECTED WEAKENING TREND. A LULL IN THE
ACTIVITY IS EXPECTED FROM LATE MORNING TO MID AFTERNOON.

UPPER LEVEL TROUGH AXIS REMAINS TO THE WEST OF THE REGION THROUGH
TONIGHT WITH Q-VECTORS INDICATING CONTINUED DYNAMIC LIFT IN THE
MID-UPPER LEVELS. HOWEVER...SIGNIFICANT CONVECTIVE OVERTURNING
THIS MORNING AND LIMITS ON INSOLATION TODAY WILL HAMPER THE
ABILITY FOR RECOVERY/DESTABILIZATION BY THIS AFTERNOON. MODELS ARE
SUGGESTING CONVECTION THIS AFTERNOON AND EVENING WILL BE MORE
SCATTERED IN NATURE...AND LIKELY ACROSS THE SOUTHEASTERN HALF OF
THE CWA WHERE GREATER INSTABILITY WILL RESIDE. AN ISOLATED SEVERE
STORM WITH HAIL/WIND WILL BE POSSIBLE GIVEN SUFFICIENT DEEP LAYER
WIND SHEAR. TEMPS TODAY WILL BE TRICKY...BUT AFTER MORNING RAIN
CLEARS OUT...SOME BREAKS IN THE CLOUDS ARE POSSIBLE THIS AFTERNOON
OVER THE WESTERN/SOUTHERN ZONES. WEAK FRONT WILL PUSH THROUGH
NORTH TEXAS TONIGHT AND HELP TO CLEAR RAIN/STORMS OUT OF THE AREA
BY MORNING. KEPT SOME LOW POPS FOR ELEVATED SHOWERS IN THE EAST ON
TUESDAY AS MID-LEVEL MOISTURE WRAPS AROUND AN INTENSIFYING UPPER
LOW OVER THE LOWER MISSISSIPPI VALLY. OTHERWISE...NW FLOW WILL BRING
DRIER/SLIGHTLY COOLER AIR INTO THE REGION FOR SOME COOLER TEMPS
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.

NEXT UPPER LEVEL TROUGH WILL BEGIN TO DEEPEN OVER THE PACIFIC NW
BY LATE IN THE WORK WEEK. INCREASING SWLY FLOW IN THE LOW-MID
LEVELS WILL RESULT IN WARMING THERMAL PROFILES...BUT GENERALLY
MILD/PLEASANT WEATHER IS EXPECTED THURSDAY AND FRIDAY. MODELS ARE
IN PRETTY POOR AGREEMENT WITH THE TIMING/POSITION/STRENGTH OF THIS
UPPER LEVEL TROUGH...WITH THE GFS CONTINUING TO BE MOST
PROGRESSIVE AND THE ECMWF THE SLOWEST. THE IMPLICATIONS OF THE
TROUGH ARE WITH THE FATE OF A STRONG COLD FRONT WHICH THE GFS
BRINGS IN ON SATURDAY AND THE ECMWF HOLDS OFF UNTIL TUESDAY. OTHER
MODELS LIE SOMEWHERE IN BETWEEN THESE TWO SOLUTIONS...AND WILL OPT
FOR A BLEND SHOWING A SUNDAY NIGHT FROPA IN NORTH TEXAS. WILL NOT
GO NEAR AS COLD AS THE GFS WHICH IS INDICATING SNOW IN THE TX
PANHANDLE AND CONTINUE TO WITH A SLIGHTLY COOLER THAN CLIMO
FORECAST THIS WEEKEND. GFS IS ALSO MOST AGGRESSIVE WITH RAIN
CHANCES AS IT SHOWS SIGNIFICANT OVERRUNNING OF SUBTROPICAL PACIFIC
MOISTURE BEHIND THE FRONT. WHILE ECMWF HAS NO FRONT IN TX AT THIS
PERIOD...THE PRESENCE OF THE UPPER TROUGH TO THE WEST AND
TROPICAL CYCLONE NORBIT NEAR BAJA MEANS SUBTROPICAL MOISTURE FEED
AND STRONGLY DIVERGENT UPPER LEVEL WIND FIELDS WILL BE PRESENT.
THIS PATTERN ALONE WARRANTS RAISING POPS TO 30 PERCENT THIS
WEEKEND...AND IF THE EARLY FRONT SOLUTION OF THE GFS COMES TO
FRUITION...POPS WILL NEED TO BE MUCH HIGHER.

TR.92



&&


.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 83 64 82 57 85 / 100 60 10 5 0
WACO, TX 85 65 85 52 87 / 80 60 10 5 0
PARIS, TX 78 63 75 51 79 / 90 80 20 5 0
DENTON, TX 82 60 80 49 85 / 100 50 5 5 0
MCKINNEY, TX 79 62 77 51 84 / 100 70 10 5 0
DALLAS, TX 82 64 81 58 84 / 100 60 10 5 0
TERRELL, TX 81 66 79 54 84 / 90 70 20 5 0
CORSICANA, TX 84 65 82 54 85 / 80 70 20 5 0
TEMPLE, TX 86 66 85 55 88 / 70 60 20 5 0

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

05/84


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