Severe Thunderstorm Warning 103, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
855 PM CDT WED MAY 6 2015

.UPDATE...
NEW TORNADO WATCH #137 ISSUED FOR YOUNG...JACK...AND MONTAGUE
COUNTIES THROUGH 2 AM CDT. THIS IS MAINLY FOR THE SUPERCELL
ENTERING SW THROCKMORTON COUNTY...AS THE ARCHER COUNTY STORM
SHOULD AFFECT CLAY COUNTY...BUT REMAIN MAINLY WEST OF MONTAGUE
COUNTY. WE EXPECT THE MAIN THREAT TO LAST THROUGH MIDNIGHT AND
GOING BY ANY UNFORESEEN CHANGES AMONGST THE HIGH-RESOLUTION
MODELS...WE WOULD THINK THE WATCH COULD BE CANCELED EARLY BY A FEW
HOURS. WE CONTINUE TO MONITOR THE THROCKMORTON STORM WHICH HAS
SHOWN WEAKENING TRENDS THE PAST 5-10 MINUTES.

05/

&&

.AVIATION...

/ISSUED 704 PM CDT WED MAY 6 2015/
/00Z TAFS/

CONCERNS...THUNDERSTORMS TO THE NORTHWEST...MVFR STRATUS.

THE BOWIE CORNERPOST HAS REMAINED OPEN...BUT SEVERE THUNDERSTORMS
WILL CONTINUE TO DISRUPT NORTHWEST ARRIVALS THIS EVENING. THE
ACTIVITY IS UNLIKELY TO GET MUCH CLOSER TO METROPLEX AIRSPACE.

A 30-35KT LLJ WILL FEED OKLAHOMA STORMS AND IN THE PROCESS WILL
SATURATE THE LAYER BENEATH AN 850MB CAP. THE RESULT WILL BE MVFR
STRATUS ARRIVING BY MIDNIGHT. THINK MOS IS TOO PESSIMISTIC WITH
IFR CEILINGS IN THE METROPLEX...THUS WILL MAINTAIN MVFR OVERNIGHT
AND THROUGHOUT THURSDAY MORNING. (TEMPO IFR MAY OCCUR AGAIN AT
WACO.)

VFR CEILINGS WILL LIKELY PREVAIL AGAIN ON THURSDAY AFTERNOON. WEAK
RIPPLES IN SOUTHWEST FLOW ALOFT WILL MAINTAIN LOW SHOWER/STORM
CHANCES...BUT WILL NOT INCLUDE ANY MENTION IN THE TAFS.

25

&&

.UPDATE...
BEST FORCING WILL REMAIN JUST OFF THE NW EDGE OF OUR CWA...BUT
STILL HAVE TO WATCH FOR SUPERCELL SPLITS AND POSSIBLE RIGHT MOVERS
FOR STEPHENS...YOUNG...JACK...MONTAGUE COUNTIES. WE PLAN TO HOLD
THESE COUNTIES IN TORNADO WATCH 135 UNTIL EXPIRATION AT 9 PM.

THE REMAINDER OF THE COUNTIES...INCLUDING EASTLAND...PALO
PINTO...PARKER...AND WISE HAVE BEEN REMOVED AT THE WATCH.

HIGH RES MODELS ARE SHOWING DISCRETE STORMS ACROSS FAR WEST TX AND
THE PERMIAN BASIN POSSIBLY BECOMING A LINEAR MCS AND ENTERING FAR
WESTERN NORTH TX AFTER 3 AM. A LOW THREAT FOR SEVERE STORMS WITH
DAMAGING WINDS...MARGINALLY SEVERE HAIL...AND HEAVY RAINFALL WILL
BE POSSIBLE WITH LATE NIGHT/EARLY THURSDAY MORNING ACTIVITY ACROSS
WESTERN NORTH TEXAS. THIS ACTIVITY SHOULD MOVE TOWARD THE NORTHERN
I-35 CORRIDOR...INCLUDING THE DFW METROPLEX BY DAYBREAK...BUT ARE
EXPECTED TO WEAKEN WITH A VEERING AND WEAKENING LOW LEVEL JET.

05/

&&

.PREV DISCUSSION... /ISSUED 248 PM CDT WED MAY 6 2015/

TORNADO WATCH 133 IS IN EFFECT ALONG AND WEST OF A NOCONA TO
WEATHERFORD TO CISCO LINE THROUGH 8 PM THIS EVENING. STORMS ARE
DEVELOPING ALONG A LAWTON TO SWEETWATER TO JUNCTION LINE WHERE THE
AIR MASS IS VERY UNSTABLE WITH VERY HIGH CAPE AND ENOUGH HELICITY
FOR SUPERCELL DEVELOPMENT AND ISOLATED TORNADOES. HAVE INCREASED
POPS ACROSS THIS AREA THROUGH THIS EVENING. ELSEWHERE...LATE
AFTERNOON CONVECTION SHOULD FAVOR AREAS GENERALLY EAST OF I-35 LIKE
YESTERDAY WITH A DECREASE IN ACTIVITY BY 10 PM.

WE WILL CONTINUE TO MAINTAIN 20-50 POPS OVER THE REGION FOR
THURSDAY THROUGH FRIDAY NIGHT BEFORE THINGS GEAR UP OVER THE
WEEKEND. ANOTHER DEEP UPPER LOW WILL MOVE THROUGH THE DESERT
SOUTHWEST FRIDAY AND INTO THE CENTRAL PLAINS SUNDAY NIGHT. THIS
SYSTEM WILL SPREAD STRONG FORCING FOR ASCENT AND UPPER DIFFLUENCE
ACROSS THE REGION OVER THE WEEKEND. ALSO...THERE WILL BE DEEP LOW
LEVEL MOISTURE IN PLACE OVER THE REGION WITH PWATS AROUND 1.90
INCHES. THUS...WE EXPECT CONSIDERABLE THUNDERSTORM ACTIVITY BOTH
SATURDAY AND SUNDAY WITH A POTENTIAL FOR SEVERE STORMS AND HEAVY
RAINFALL THAT COULD RESULT IN FLASH FLOODING PROBLEMS AND RIVER
RISES...ESPECIALLY ON SUNDAY.

AS THE UPPER LOW MOVES THROUGH THE CENTRAL PLAINS SUNDAY NIGHT...A
COLD FRONT WILL SWEEP THROUGH NORTH TEXAS EARLY MONDAY AND AROUND
MID CENTRAL TEXAS ON MONDAY MORNING. THERE WILL BE SOME CONVECTION
ALONG THE FRONT THAT WILL MOVE SOUTH WITH IT. HOWEVER...WE WILL
MAINTAIN CHANCE POPS GENERALLY SOUTH OF I-20 ON TUESDAY.

THERE ARE SOME DISCREPANCIES BETWEEN THE ECMWF AND GFS CONCERNING
HOW FAR SOUTH THE FRONT GOES...HOW FAST IT RETURNS AND
PRECIPITATION NEXT WEEK. THE GFS SEEMS TO BE THE OUTLIER WHEN
COMPARED TO THE ECMWF AND CANADIAN MODELS...THUS HAVE WEIGHTED THE
MID WEEK FORECAST TOWARD THE MORE CONSISTENT MODELS WHICH KEEP
THE COLD FRONT TO THE SOUTH TUESDAY THROUGH WEDNESDAY BEFORE
BRINGING IT BACK NORTH. 75

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  68  82  69  81  70 /  30  40  30  40  40
WACO, TX              69  82  69  83  70 /  20  30  30  40  30
PARIS, TX             66  79  68  81  69 /  20  40  30  30  50
DENTON, TX            67  81  69  80  69 /  40  50  40  40  40
MCKINNEY, TX          67  80  69  80  69 /  20  40  30  40  40
DALLAS, TX            68  83  69  82  70 /  30  30  30  40  30
TERRELL, TX           68  82  68  82  69 /  20  30  30  40  30
CORSICANA, TX         68  82  69  83  70 /  20  30  30  40  30
TEMPLE, TX            70  83  69  83  70 /  20  30  20  40  30
MINERAL WELLS, TX     67  80  68  80  69 /  40  50  40  50  40

&&

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

&&

25/05

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
914 PM CDT WED MAY 6 2015

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-071100-
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-
914 PM CDT WED MAY 6 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL TEXAS.

.DAY ONE...TONIGHT.
SEVERE THUNDERSTORMS WILL BE POSSIBLE LATE THIS EVENING AND INTO
THE EARLY MORNING HOURS...PRIMARILY ALONG AND NORTHWEST OF A LINE
FROM CISCO...TO MINERAL WELLS...TO GAINESVILLE. THE PRIMARY
SEVERE WEATHER THREAT IS LARGE HAIL AND DAMAGING WINDS...BUT
A TORNADO WILL ALSO BE POSSIBLE...PARTICULARLY IN JACK...
MONTAGUE...AND YOUNG COUNTIES.

THUNDERSTORMS WILL BE POSSIBLE ELSEWHERE THIS EVENING AND
OVERNIGHT. LOCALLY HEAVY RAINFALL AND CLOUD-TO-GROUND LIGHTNING
WOULD BE THE PRIMARY THREATS FROM THESE STORMS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.
THERE IS A CHANCE OF THUNDERSTORMS THROUGHOUT NORTH TEXAS EVERY
DAY THURSDAY THROUGH TUESDAY...ALTHOUGH NOT ALL AREAS WILL SEE
THUNDERSTORMS EACH DAY. SOME ISOLATED SEVERE WEATHER IS POSSIBLE
THURSDAY THROUGH FRIDAY BUT BETTER SEVERE WEATHER AND HEAVY
RAINFALL CHANCES WILL OCCUR ON SATURDAY AND SUNDAY. OTHERWISE...
THE MAIN THREATS WITH ANY STORMS WILL BE LOCALLY HEAVY RAINFALL
AND FREQUENT CLOUD-TO-GROUND LIGHTNING.

.SPOTTER INFORMATION STATEMENT...
LIMITED SPOTTER ACTIVATION MAY BE REQUESTED LATE THIS EVENING...
PRIMARILY IN JACK...MONTAGUE...AND YOUNG COUNTIES.