River Flood Warning 81, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
710 AM CDT FRI APR 29 2016

.AVIATION...
/12Z TAFS/

PRIMARY CONCERN...THUNDER/SEVERE POTENTIAL THIS AFTERNOON.

A WARM FRONT HAS PUSHED NORTH OF THE DALLAS/FORT WORTH
METROPLEX...USHERING IN RICH GULF MOISTURE. AIDED BY A NOCTURNAL
LLJ...SOME WARM ADVECTION SHOWERS ARE OCCURRING NORTH OF THE
SURFACE BOUNDARY...IN AREAS GENERALLY NORTH AND EAST OF METRO TAF
SITES. EARLY MORNING THUNDERSTORMS THAT AFFECTED PORTIONS OF NORTH
TEXAS ARE NOW IMPACTING THE ARKLATEX...AND ADDITIONAL STORMS ARE
UNLIKELY AT TAF SITES THE REMAINDER OF THE MORNING.

WINDS HAVE VEERED TO THE SOUTH...AND THE NOCTURNAL BOUNDARY LAYER
IS STEADILY SATURATING FROM THE TOP DOWN. ADDITIONAL MOIST
ADVECTION THIS MORNING WILL DROP CEILINGS BELOW FL010 AT TIMES...
AND THE VISIBILITY MAY BRIEFLY DIP INTO THE MVFR CATEGORY BEFORE
THE LATE APRIL SUN WARMS THE SURFACE LAYER.

A CAP IS CURRENTLY IN PLACE...WHICH WILL INITIALLY PRECLUDE
SURFACE-BASED STORMS...BUT AS AN APPROACHING UPPER-LEVEL
DISTURBANCE PROVIDES LIFT...THIS CAP SHOULD GRADUALLY ERODE. IN
THE MEANTIME...A FEW ELEVATED SHOWERS WILL BE POSSIBLE BEFORE
UPDRAFTS BECOME ROOTED IN THE BOUNDARY LAYER. THUNDERSTORMS ARE
EXPECTED TO DEVELOP DURING THE EARLY AFTERNOON...PERHAPS JUST WEST
OF THE I-35 CORRIDOR. THE MOST LIKELY WINDOW FOR THUNDERSTORM
IMPACTS AT TAF SITES WILL BE FROM MID-AFTERNOON THROUGH SUNSET.
SOME OF THESE STORMS MAY BE SEVERE...WITH LARGE HAIL AND DAMAGING
WINDS THE PRIMARY THREATS. TORNADIC SUPERCELLS WILL ALSO BE
POSSIBLE. THE ACTIVITY WOULD BE EAST OF THE I-35 CORRIDOR BY
NIGHTFALL...AFTER WHICH VFR CONDITIONS WILL PREVAIL.

WINDS WILL VEER TO THE SOUTHWEST TONIGHT...AND A SHIFT TO NORTH
FLOW WILL LIKELY OCCUR AFTER DAYBREAK SATURDAY MORNING. THIS WIND
SHIFT HAS BEEN INTRODUCED INTO THE EXTENDED PORTION OF THE DFW
TAF.

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&&

.PREV DISCUSSION... /ISSUED 407 AM CDT FRI APR 29 2016/
A WARM FRONT WILL CONTINUE TO LIFT NORTH ACROSS THE REGION THIS
MORNING IN RESPONSE TO DEEP SURFACE LOW PRESSURE CURRENTLY
CENTERED ACROSS THE WESTERN TEXAS PANHANDLE. THIS WARM FRONT HAS
BEEN THE CATALYST FOR SHOWERS AND THUNDERSTORMS OVERNIGHT AND
WILL CONTINUE TO A FOCUS FOR STORM INITIATION THROUGH THE MORNING.
IT IS DIFFICULT TO SAY EXACTLY WHERE THE WARM FRONT WILL END UP
THIS AFTERNOON...BUT IT SHOULD BE IN THE VICINITY OF THE RED
RIVER. THIS WILL LEAVE ALL OF NORTH AND CENTRAL TEXAS IN VERY
MOIST AND UNSTABLE AIR. ALTHOUGH SOME SHOWERS AND STORMS MAY
DEVELOP IN THE WARM SECTOR THROUGH THE MORNING AS LARGE SCALE LIFT
ASSOCIATED WITH AN APPROACHING 4 CORNERS LOW INCREASES...STORMS
ARE MOST LIKELY TO DEVELOP DURING THE AFTERNOON ON AN EASTWARD
MOVING DRYLINE. STORMS THAT DEVELOP ALONG THE DRYLINE WILL HAVE A
GOOD POTENTIAL TO BECOME SEVERE WITH MORE THAN SUFFICIENT
INSTABILITY AND ADEQUATE VERTICAL SHEAR TO SUSTAIN TALL UPDRAFTS.
THEREFORE...LARGE HAIL AND DAMAGING WINDS WILL BE THE PRIMARY
HAZARDS. A FEW TORNADOES WILL ALSO BE POSSIBLE...ESPECIALLY NEAR
THE TRIPLE POINT WHICH WILL LIKELY BE SOMEWHERE WEST/NORTHWEST OF
THE CWA.

STORMS WILL MOVE EAST OFF THE DRYLINE THROUGH THE AFTERNOON AND
END UP GENERALLY ALONG AND EAST OF INTERSTATE 35 BY THIS EVENING.
THE SEVERE POTENTIAL WILL CONTINUE THIS EVENING ALONG WITH A
THREAT OF HEAVY RAINFALL AND SOME LOCALIZED FLOODING. WE HAVE
DECIDED NOT TO ISSUE A FLASH FLOOD WATCH AT THIS POINT IN TIME
SINCE THE UPPER LOW IS PROGGED TO LIFT TO THE CENTRAL PLAINS
OVERNIGHT/EARLY SATURDAY MORNING WHICH WILL SHIFT THE HEAVIEST
RAINFALL INTO EAST TEXAS.

DRIER AND COOLER AIR WILL BEGIN TO WORK IN FROM THE NORTHWEST
EARLY SATURDAY MORNING BEHIND A COLD FRONT. THE FRONT SHOULD MOVE
THROUGH ALL OF THE FORECAST AREA BY SUNSET SATURDAY AND BRING AN
END TO ALL PRECIPITATION CHANCES.

BRIEF SHORTWAVE RIDGING WILL TAKE PLACE OVER THE REGION SATURDAY
NIGHT THROUGH SUNDAY AND BRING DRY AND PLEASANT WEATHER.
HOWEVER...THE RIDGE AXIS WILL QUICKLY SHIFT EAST SUNDAY NIGHT AS
ANOTHER SHORTWAVE APPROACHES FROM THE WEST. ENERGY AND ELEVATED
MOISTURE FROM THIS SYSTEM WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS SUNDAY NIGHT THROUGH TUESDAY. HOWEVER...SINCE LOW
LEVEL MOISTURE WILL BE LIMITED...STORMS WILL BE ELEVATED AND
GENERALLY BELOW SEVERE LIMITS.

ONCE THE EARLY WEEK SHORTWAVE DEPARTS...A RIDGE OF HIGH PRESSURE
WILL AMPLIFY OVER THE REGION WEDNESDAY THROUGH FRIDAY AND BRING
RAIN-FREE WEATHER TO ALL OF NORTH AND CENTRAL TEXAS.

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&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH    81  65  80  58  78 /  70  40  10   5   5
WACO                82  64  83  58  80 /  70  50  20  10   5
PARIS               78  65  78  57  79 /  80  70  30  10   5
DENTON              79  61  79  54  76 /  60  40  10   5   5
MCKINNEY            79  63  79  56  77 /  70  50  10  10   5
DALLAS              81  65  82  59  79 /  70  50  10  10   5
TERRELL             81  65  81  57  79 /  80  60  20  10   5
CORSICANA           82  66  83  60  80 /  70  60  20  10   5
TEMPLE              81  64  83  60  81 /  70  50  20  10   5
MINERAL WELLS       81  58  79  54  75 /  50  20   5   5   5

&&

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

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
515 AM CDT FRI APR 29 2016

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-301100-
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-
515 AM CDT FRI APR 29 2016

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH AND CENTRAL TEXAS.

.DAY ONE...TODAY AND TONIGHT.
ALTHOUGH THUNDERSTORMS WILL BE POSSIBLE THIS MORNING...THEY ARE
MORE LIKELY TO OCCUR DURING THE AFTERNOON WHEN A DRYLINE INVADES
FROM THE WEST. IN ADVANCE OF THE BOUNDARY...A VERY UNSTABLE
ATMOSPHERE WILL BE LARGELY UNCAPPED AT PEAK HEATING...AS AN
APPROACHING UPPER-LEVEL DISTURBANCE PROVIDES LIFT TO HELP INITIATE
STORMS. STRONG VERTICAL WIND SHEAR WILL AID IN STORM MAINTENANCE
AND MAY RESULT IN SUPERCELLS CAPABLE OF VERY LARGE HAIL...
DAMAGING WINDS...AND TORNADOES.

THE ACTIVITY WILL SHIFT EAST OF THE I-35 CORRIDOR THIS EVENING.
THE POTENTIAL FOR SEVERE THUNDERSTORMS WILL CONTINUE AFTER DARK
BUT GRADUALLY DIMINISH DURING THE OVERNIGHT HOURS. AS THE NIGHT
PROGRESSES...TRAINING CELLS MAY ENHANCE THE THREAT OF FLOODING...
PARTICULARLY IN EAST TEXAS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.
A COLD FRONT WILL EVENTUALLY OVERTAKE THE DRYLINE...AND THE
RESULTING BOUNDARY MAY LINGER ACROSS CENTRAL AND EAST TEXAS
SATURDAY AFTERNOON. ANOTHER ROUND OF THUNDERSTORMS WILL BE
POSSIBLE ALONG THE STALLED FRONT...BUT A LACK OF FORCING MAY LIMIT
THE EXTENT AND INTENSITY OF THE ACTIVITY. SEVERE WEATHER IS NOT
EXPECTED.

THE NEXT STORM SYSTEM WILL APPROACH EARLY NEXT WEEK. THUNDERSTORM
CHANCES WILL RETURN AS EARLY AS SUNDAY NIGHT AND CONTINUE ON
MONDAY...BEFORE COMING TO AN END ON TUESDAY. THE SEVERE THREAT
DURING THIS PERIOD APPEARS LOW.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION IS LIKELY THIS AFTERNOON AND EVENING...
ESPECIALLY ALONG AND EAST OF THE I-35 CORRIDOR.

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