Flash Flood Warning 323, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED FOR AVIATION
NATIONAL WEATHER SERVICE FORT WORTH TX
640 AM CDT THU JUL 5 2007

.AVIATION...
SOMEWHAT DIFFICULT FORECAST WITH CIGS BOUNCING AROUND BETWEEN IFR
AND VFR AROUND THE METROPLEX WITH APPARENTLY NO RHYME OR REASON.
WACO IS ALSO FLUCTUATING WITH CIGS AS LOW AS 200FT. WILL SHOW
MVFR/VFR ACROSS THE METRO THROUGH 15Z BEFORE HAVING MVFR PREVAIL
AFTERWARDS.  BELIEVE WACO WILL HAVE THE BEST CHANCE OF
RAIN...ESPECIALLY IN THE MORNING AND EARLY AFTERNOON HOURS.  METRO
SITES WILL HAVE SOME LIGHT SHRA THIS MORNING...HARDLY WORTH
MENTIONING...WITH MORE SUBSTANTIAL CONVECTION OCCURRING THIS
AFTERNOON.  THUNDER WILL BE RATHER LIMITED TODAY AND WILL SHOW
MOSTLY SHOWERS BUT VCTS IS POSSIBLE DURING MAX HEATING THIS
AFTERNOON. CONFIDENCE TOO LOW TO PICK A TIME...AND BELIEVE THAT
PERIODS OF +SHRA WITH NO TS IS MORE LIKELY BETWEEN 11 AM AND 4 PM.
THINGS SHOULD QUIET DOWN LATE THIS AFTERNOON AND INTO THE EVENING
WITH VFR PREVAILING BEFORE MORE MVFR CIGS DEVELOP AROUND MIDNIGHT.
WACO WILL HAVE A CHANCE OF RAIN/STORMS AFTER MIDNIGHT AS LOW REMAINS
OVER CENTRAL TEXAS AND WILL SHOW VCTS FOR NOW.  TR.92

&&

.DISCUSSION...
SPIN BETWEEN KILLEEN AND SAN MARCOS IS EVIDENT IN REGIONAL 88-D
MOSAIC. SEVERAL BANDS OF PRECIP ARE DEVELOPING ALONG THE NORTHERN
PERIPHERY OF THE CIRCULATION OVER OUR SOUTHERN/EASTERN CWA...WITH THE
MOST WIDESPREAD PRECIP REMAINING ALONG THE GULF COAST.

MEANWHILE...ANOTHER CIRCULATION NOTED IN WATER VAPOR OVER THE
OK/TX PANHANDLES HAS HELPED TRIGGER A COUPLE OF CONVECTIVE COMPLEXES
IN THE TX PANHANDLE AND WESTERN OK OVERNIGHT. THIS ACTIVITY IS
FEEDING SOUTHWESTWARD ALONG AN INSTABILITY TONGUE AND IS NOT
EXPECTED TO SIGNIFICANTLY IMPACT NORTH TEXAS. HOWEVER...OUTFLOW
BOUNDARIES FROM THE CONVECTION IN SW OKLAHOMA MAY PLAY A ROLE IN
LATE MORNING/AFTERNOON CONVECTION TODAY OVER NORTHWEST PORTIONS OF THE
FORECAST AREA.

00Z RUN OF 4.0KM NMM-WRF APPEARS TO HAVE INITIALIZED WELL AND HAS
A GOOD HANDLE ON THE ONGOING PRECIP /BOTH IN THE TX PANHANDLE AND
ALONG THE TX GULF COAST/. NMM-WRF PROGS SUGGEST THE SOUTHERN AND
EASTERN PORTIONS OF THE CWA WILL HAVE THE GREATEST CHANCES OF
HEAVY RAINFALL TODAY...AS THE UPPER LEVEL CIRCULATION GRADUALLY
MOVES NORTHEAST. ELSEWHERE ACROSS NORTH TEXAS...BANDS OF SCATTERED
T-STORMS ARE EXPECTED. WITHIN THESE SCATTERED BANDS...ANY STORM
COULD PRODUCE ENOUGH HEAVY RAINFALL IN A SHORT PERIOD OF TIME TO
EXACERBATE THE OVERWHELMED SOILS...AND RESULT IN FLASH FLOODING.
HOWEVER...THE GREATEST LIKELIHOOD OF WIDESPREAD FLASH FLOODING
WILL BE ROUGHLY ALONG AND EAST OF A LINE FROM KILLEEN TO PARIS
TODAY.

THE CANADIAN AND UKMET HAVE COME IN LINE WITH THE GFS IN REGARDS
TO THE EVOLUTION OF OUR PESKY UPPER LOW. THE 3 MODELS NOW DRAW OUR
LOW INTO NORTHEAST TEXAS...SHEARING IT ACROSS THE ARKLATEX BEFORE
CARRYING IT OFF TOWARD THE LOWER MISSISSIPPI VALLEY.

AS THE UPPER LOW IS DRAWN UP INTO NORTHEAST TEXAS LATE TONIGHT AND
INTO EARLY FRIDAY MORNING...HEAVY RAINFALL WILL BE POSSIBLE OVER
THE EASTERN AND NORTHEASTERN PORTIONS OF THE CWA.

GFS AND CANADIAN CARRY THE MAIN ENERGY FROM OUR PERSISTENT LOW
INTO ARKANSAS/TENNESSEE...BUT MAINTAIN TROFFINESS OVER OKLAHOMA
AND NORTH TEXAS FOR SEVERAL DAYS. WITH THE BULK OF THE FORCING WELL
TO OUR EAST...DEEP MOISTURE IN PLACE...AND A WEAKNESS IN THE FLOW
OVER THE AREA...DIURNAL STORMS WILL BE POSSIBLE SAT-MON. AS A
RESULT...HAVE KEPT SLIGHT CHANCE POPS DURING THE DAYTIME PERIODS
WITH 10 POPS FROM 00-12Z.

NORTHWEST FLOW REGIME SETS UP ACROSS THE SOUTH CENTRAL PLAINS BY
THE MIDDLE OF NEXT WEEK. IF THIS PATTERN COMES TO
FRUITION...SEVERAL WAVES OF NOCTURNAL MCS ACTIVITY COULD BE
ANTICIPATED OVER KS/OK/TX...PERHAPS BRINGING MORE HEAVY RAINFALL TO
THE REGION.

THERE IS STILL UNCERTAINTY IN THE PATTERN OVER THE NEXT 7
DAYS....WHICH HINGE ON THE EVOLUTION OF THE UPPER LOW CIRCULATION
THAT HAS PLAGUED OUR REGION.

SCHULTZ

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  86  70  84  71  90 /  70  50  60  40  20
WACO, TX              83  72  85  71  91 /  70  60  70  40  30
PARIS, TX             84  71  84  70  89 /  80  50  60  50  20
DENTON, TX            87  70  84  69  90 /  70  50  50  40  20
MCKINNEY, TX          84  71  84  70  91 /  70  50  60  40  20
DALLAS, TX            85  72  84  73  90 /  70  50  60  40  20
TERRELL, TX           84  71  84  72  89 /  80  50  60  50  20
CORSICANA, TX         83  73  84  71  89 /  80  60  70  40  30
TEMPLE, TX            84  72  85  70  89 /  80  60  70  40  30

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
FLASH FLOOD WATCH THROUGH FRIDAY EVENING FOR THE FOLLOWING
ZONES:
TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
502 AM CDT THU JUL 5 2007

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-061015-
MONTAGUE-COOKE-GRAYSON-FANNIN-LAMAR-YOUNG-JACK-WISE-DENTON-COLLIN-
HUNT-DELTA-HOPKINS-STEPHENS-PALO PINTO-PARKER-TARRANT-DALLAS-
ROCKWALL-KAUFMAN-VAN ZANDT-RAINS-EASTLAND-ERATH-HOOD-SOMERVELL-
JOHNSON-ELLIS-HENDERSON-COMANCHE-MILLS-HAMILTON-BOSQUE-HILL-
NAVARRO-FREESTONE-ANDERSON-LAMPASAS-CORYELL-BELL-MCLENNAN-FALLS-
LIMESTONE-LEON-MILAM-ROBERTSON-
502 AM CDT THU JUL 5 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...
A FLASH FLOOD WATCH IS IN EFFECT FOR ALL AREAS TODAY THROUGH
FRIDAY EVENING.

SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS CAPABLE OF
PRODUCING HEAVY RAINFALL WILL BE LIKELY TODAY AND TONIGHT.
RAINFALL TOTALS OF 1 TO 3 INCHES CAN BE EXPECTED...WITH ISOLATED
HIGHER AMOUNTS. ANY ADDITIONAL HEAVY RAINFALL WILL QUICKLY LEAD TO
FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...
SHOWERS AND THUNDERSTORMS CAPABLE OF PRODUCING HEAVY RAINFALL
WILL CONTINUE FRIDAY.

RAIN CHANCES WILL TAPER OFF FROM NORTHWEST TO SOUTHEAST FRIDAY
NIGHT. AREAS ALONG AND SOUTHEAST OF A LINE FROM PARIS TO KILLEEN
WILL HAVE THE GREATEST CHANCE OF SHOWERS AND THUNDERSTORMS LATE
FRIDAY NIGHT AND EARLY SATURDAY MORNING.

THUNDERSTORMS WILL BE POSSIBLE DAILY ACROSS ALL OF NORTH TEXAS
SATURDAY AFTERNOON THROUGH WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...
LIMITED SPOTTER ACTIVATION MAY BE REQUESTED.

SCHULTZ