Severe Thunderstorm Warning 341, NWS Fort Worth, TX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
1252 PM CDT FRI OCT 30 2015

.AVIATION...
/18Z TAFS/

WIDESPREAD RAINFALL WILL CONTINUE TO IMPACT ALL OF THE MAJOR
AIRPORTS THROUGH THIS EVENING...WITH MINOR DIFFERENCES IN TIMING
AND INTENSITY. RIGHT NOW...HEAVIEST OF THE RAIN HAS JUST MOVED
EAST OF THE WACO AREA AND THEY SHOULD SEE A LITTLE LULL IN THE
ACTIVITY. WILL PREVAIL -RA AND MVFR CIGS THROUGH THE NEXT FEW
HOURS. IN THE METROPLEX...THERE HAS BEEN AN UPTICK IN THE RAIN
OVER THE LAST HOUR BUT GENERALLY MVFR CONDITIONS WILL PREVAIL IN
-RA. OVER THE NEXT SEVERAL HOURS...SCATTERED SHOWERS AND A FEW
THUNDERSTORMS WILL MOVE EAST AND AFFECT MOST OF THE AREA. WILL
HAVE THE BEST TIMING FROM 21-01Z OR 5 TO 9 PM. SOME TEMPO IFR
CONDITIONS POSSIBLE IN HEAVY RAIN. RAIN SHOULD TAPER OFF TONIGHT
AS THE COLD FRONT APPROACHES BUT IFR CIGS REMAIN LIKELY AFTER
MIDNIGHT. WINDS WILL SHIFT AROUND TO THE NORTHWEST TOMORROW
MORNING WITH GRADUAL IMPROVEMENT IN CIGS THROUGH THE DAY.

DUNN

&&

.UPDATE...
NUMEROUS SHOWERS AND A FEW THUNDERSTORMS CONTINUE TO MOVE
NORTH/NORTHEAST ACROSS NORTH TEXAS LATE THIS MORNING. THE
STRONGEST ACTIVITY IS STILL IN THE WARM SECTOR AROUND AND EAST OF
AUSTIN. THIS ACTIVITY WILL CONTINUE TO WEAKEN AS IT MOVES NORTH
INTO MORE STABLE AIR. HOWEVER...LOCATIONS SOUTH OF A LINE FROM
TEMPLE TO CENTERVILLE WILL GET DEEPER INTO THE WARM SECTOR
THROUGH THE AFTERNOON AND WILL SEE SOME PERIODS OF HEAVY RAINFALL
AND THUNDERSTORMS WITH A POTENTIAL FOR SOME LOCALIZED FLOODING.
SINCE THE FLOODING IS EXPECTED TO BE LOCALIZED...WE WILL NOT ISSUE
A FLASH FLOOD WATCH FOR THE AFTERNOON. WE WILL CONTINUE TO ASSESS
THE FLOODING POTENTIAL FOR TONIGHT.

THERE IS STILL A POTENTIAL FOR SEVERE STORMS THROUGH THE
AFTERNOON....ESPECIALLY ACROSS THE EXTREME SOUTHERN ZONES WHERE
INSTABILITY WILL SLOWLY INCREASE THROUGH THE AFTERNOON.

WE EXPECT PRECIPITATION TO END FROM WEST TO EAST DURING THE
EVENING HOURS AS THE UPPER LOW LIFTS ACROSS FAR WEST TEXAS AND A
COLD FRONT ENTERS THE REGION. WE WILL STILL SEE PERIODS OF RAIN
AND THUNDERSTORMS OVERNIGHT FOR LOCATIONS GENERALLY EAST OF THE
INTERSTATE 35 CORRIDOR. THE PRECIPITATION ACROSS THE EASTERN
ZONES SHOULD EXIT INTO EAST TEXAS AFTER SUNRISE SATURDAY AS THE
UPPER TROUGH AXIS MOVES EAST ACROSS THE REGION.

WILL MAKE SOME CHANGES TO EVENING/OVERNIGHT POPS AND ADJUST THE
QPF AMOUNTS FOR THIS UPDATE. WILL ALSO ADJUST HOURLY TEMP AND
DEWPOINT GRIDS.

79

&&

.PREV DISCUSSION... /ISSUED 345 AM CDT FRI OCT 30 2015/

...1 TO 3 INCHES OF RAINFALL POSSIBLE TODAY THROUGH SATURDAY
MORNING...

WATER VAPOR LOOP SHOWS AN UPPER TROUGH OVER SOUTHEAST ARIZONA
EARLY THIS MORNING WHILE REGIONAL 88D RADAR VAD WIND PROFILES SHOW
A DEEP AND STRONG LOW LEVEL JET EXTENDING FROM THE NORTHWEST GULF
OF MEXICO TO THE RED RIVER. THE WWA ASSOCIATED WITH THIS LLJ IS
MOVING LOW CLOUDS NORTHWARD AND HELPING TO INCREASE INSTABILITY
AHEAD OF THE UPPER SYSTEM. AS THE UPPER TROUGH MOVES EAST TODAY...
FORCING FOR ASCENT WILL INCREASE FROM WEST TO EAST AND SPREAD
CONVECTION TO THE I-35 CORRIDOR BY MIDDAY AND INTO THE EASTERN
COUNTIES THIS AFTERNOON AND EVENING.

THIS SYSTEM WILL HAVE SOME STRONG DYNAMICS ASSOCIATED WITH IT
TODAY THROUGH TONIGHT...I.E. A STRONG DIFFLUENT JET SPREADING OVER
THE REGION...PWATS CLIMBING TO AROUND 2 INCHES AND 35 TO 50 KNOTS
OF 0-3 KM BULK SHEAR. THE BEST CAPE WILL BE WEST OF I-35 THIS
AFTERNOON AND EVENING. AS FOR SEVERE THUNDERSTORMS...THERE IS A
MARGINAL RISK ACROSS MUCH OF THE CWA THIS AFTERNOON/EVENING AND A
SLIGHT RISK OVER AREAS SOUTH OF I-20 AND WEST OF I-35 WHERE LOW
VALUE CAPE WILL BE MAXIMIZED. HAIL AND DAMAGING WINDS ARE THE
PRIMARY HAZARDS. HOWEVER...BECAUSE OF THE STRONG LOW LEVEL
SHEAR... 0-3 KM HELICITY WILL PEAK 500-1000 M2/S2 ALONG THE
I-35/45 CORRIDORS THIS AFTERNOON...CAN NOT RULE OUT A BRIEF
TORNADO TO TWO.

THERE IS A HEAVY RAINFALL/FLOODING POTENTIAL WITH THIS
SYSTEM...BUT CONSIDERING HOW FAST THE CONVECTIVE ELEMENTS WILL BE
MOVING...DO NOT THINK MULTIPLE ROUNDS OF HEAVY PRECIPITATION WILL
OCCUR OVER A LARGE ENOUGH AREA TO WARRANT ISSUING A MULTI-COUNTY
FLASH FLOOD WATCH. HOWEVER...IF CONVECTIVE BAND SETS UP OVER
SOUTHEAST HILL COUNTY OR NAVARRO COUNTY WHERE THE GROUND REMAINS
WET...THEN FLASH FLOODING WILL LIKELY OCCUR. OUR BEST GUESS ON
RAIN AMOUNTS TODAY THROUGH TONIGHT IS 1 TO 3 INCHES WITH LOCALIZED
HIGHER AMOUNTS UP TO 5 INCHES.

THE RAIN WILL BE ENDING WEST TO EAST ON SATURDAY AS A COLD FRONT
MOVES THROUGH THE REGION. BY SATURDAY EVENING...MOST OF THE RAIN
WILL BE IN EAST TEXAS...BUT WILL LINGER A SLIGHT CHANCE OVER THE
EASTERN TIER OF COUNTIES SATURDAY NIGHT.

SUNDAY THROUGH TUESDAY EVENING WILL BE DRY AND SEASONABLY MILD AS
SHORT WAVE RIDGING RETURNS. OUR NEXT WEATHER SYSTEM WILL BE
AMPLIFYING DOWN THE WEST COAST EARLY NEXT WEEK...THEN MOVING INTO
THE DESERT SOUTHWEST BY LATE WEEK. THIS WILL BE A SIMILAR RAIN
EVENT AS TODAYS WITH SHOWERS AND THUNDERSTORMS RETURNING WEDNESDAY
THROUGH NEXT FRIDAY. 75

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  70  63  71  55  73 /  90  90  30  10  10
WACO, TX              73  65  75  54  73 / 100  90  40  10  10
PARIS, TX             70  61  70  54  72 /  90  90  70  10  10
DENTON, TX            68  60  70  52  72 /  90  90  30  10   5
MCKINNEY, TX          69  62  70  53  72 /  90  90  30  10  10
DALLAS, TX            71  64  72  56  73 /  90  90  30  10  10
TERRELL, TX           72  63  72  55  72 /  90  90  50  10  10
CORSICANA, TX         74  65  75  57  73 / 100  90  60  10  10
TEMPLE, TX            75  65  75  55  74 / 100  90  40  10  10
MINERAL WELLS, TX     69  57  69  50  73 /  90  80  20  10   5

&&

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

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
330 AM CDT FRI OCT 30 2015

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-311100-
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-
330 AM CDT FRI OCT 30 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL TEXAS.

.DAY ONE...TODAY AND TONIGHT.
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED
ACROSS ALL OF NORTH TEXAS THROUGH TONIGHT. WIDESPREAD RAINFALL
AMOUNTS OF 1 TO 3 INCHES CAN BE EXPECTED. A FEW STORMS MAY BE
CAPABLE OF PRODUCING LARGE HAIL AND DAMAGING WINDS MAINLY
SOUTHWEST OF A CISCO TO CENTERVILLE LINE. GIVEN THE STRONG
VERTICAL WIND SHEAR...A FEW TORNADOES WILL ALSO BE POSSIBLE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.
SCATTERED THUNDERSTORMS WILL END FROM WEST TO EAST SATURDAY
AFTERNOON THROUGH SATURDAY NIGHT.

THUNDERSTORM CHANCES WILL RETURN TO ALL OF NORTH TEXAS WEDNESDAY
AND CONTINUE THROUGH THURSDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION MAY BE REQUESTED THIS AFTERNOON AND EVENING
MAINLY SOUTHWEST OF A CISCO TO CENTERVILLE LINE.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
1213 PM CDT FRI OCT 30 2015

TXZ174-301800-
MILAM TX-
1213 PM CDT FRI OCT 30 2015

...SIGNIFICANT WEATHER ADVISORY FOR MILAM COUNTY UNTIL 100 PM CDT...

AT 1213 PM CDT...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM
OVER ROCKDALE...MOVING NORTHEAST AT 40 MPH.

WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
ROCKDALE...CAMERON...THORNDALE AND MILANO.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THIS STORM...AND MAY LEAD
TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

&&

A TORNADO WATCH REMAINS IN EFFECT UNTIL 700 PM CDT FOR CENTRAL TEXAS.

LAT...LON 3067 9724 3100 9675 3097 9677 3093 9676
      3092 9673 3090 9672 3091 9669 3087 9670
      3081 9664 3078 9665 3078 9663 3074 9663
      3073 9662 3046 9715
TIME...MOT...LOC 1713Z 236DEG 35KT 3061 9701

30