Hail in Texas, April 27 to 28, 2014

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
650 AM CDT SUN APR 27 2014

.AVIATION...
/12Z TAFS/

CONCERNS...STORMS CHANCES...CEILINGS...CROSSWINDS.

STORM CHANCES...
DESPITE SIGNIFICANT LAPSE RATES (AROUND 8C/KM) ABOVE A LINGERING
INVERSION...THE BEST FORCING FOR ASCENT REMAINED WELL WEST OF TAF
SITES OVERNIGHT...AND THIS INSTABILITY HAS YET TO BE REALIZED. A
FRONTAL BOUNDARY IS APPROACHING WICHITA FALLS...WITH SHOWERS AND
THUNDERSTORMS ALONG IT. A PREFRONTAL TROUGH HAS REMAINED AROUND
60 MILES AHEAD OF THE FRONT THROUGHOUT THE NIGHT. ONCE THE
CONVERGENCE ALONG THIS WIND SHIFT ENTERED THE DEEPER MOISTURE
ACROSS NORTH TEXAS...CONVECTIVE INITIATION BEGAN ALONG IT AS WELL.
DESPITE THIS MECHANICAL FORCING IN THE LOW-LEVELS...FWD 12Z RAOB
MAINTAINED A STOUT CAP (12F). AS A RESULT...THE STORMS THIS
MORNING ARE UNLIKELY TO TAP THE BUOYANT SURFACE LAYER.
NONETHELESS...THE STEEP LAPSE RATES ALOFT SHOULD ALLOW FOR SOME
UPDRAFTS SUPPORTIVE OF HAIL. THE POTENTIAL WINDOW FOR DIRECT
IMPACTS AT METROPLEX TAF SITES WILL BE SMALL (GENERALLY 8-10 AM
CDT)...BUT BOTH NORTH AND WEST DEPARTURES MAY BE ADVERSELY
AFFECTED THROUGHOUT THE MORNING PUSH. THE MAIN FRONT WILL PUSH
EAST OF THE I-35 CORRIDOR LATE THIS MORNING...BRINGING AN END TO
THE STORM CHANCES.

CEILINGS AND CROSSWINDS...
MVFR CEILINGS WILL PREVAIL UNTIL A MID-MORNING PREFRONTAL TROUGH
VEERS THE WINDS WEST OF SOUTH. THE LATE MORNING FRONTAL PASSAGE
WILL VEER THE WINDS FURTHER...AND SPEEDS WILL INCREASE. WITH
SUSTAINED SPEEDS OVER 20KTS AND FREQUENT GUSTS EXCEEDING 30KTS...
THESE SOUTHWEST WINDS WILL CAUSE SIGNIFICANT CROSSWIND ISSUES AT
LOVE FIELD AND LIMIT THE AVAILABILITY OF THE DIAGONALS AT DFW THIS
AFTERNOON.

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&&

.PREV DISCUSSION... /ISSUED 310 AM CDT SUN APR 27 2014/
A PACIFIC COLD FRONT WILL CONTINUE TO SURGE THROUGH WEST
TEXAS EARLY THIS MORNING AND WILL OVERTAKE THE DRYLINE BEFORE IT
ARRIVES IN NORTH TEXAS. THE COLD FRONT WILL REACH THE WESTERN CWA
BETWEEN 6 AND 7 AM AND PROGRESS STEADILY EASTWARD AS A POWERFUL
UPPER LOW LIFTS FROM SOUTHERN COLORADO/NORTHERN NEW MEXICO TO
NORTHERN KANSAS BY THIS AFTERNOON. THE 00Z FWD SOUNDING INDICATED
A STOUT (10 DEGREE) CAP IN PLACE WITH NEARLY DRY ADIABATIC LAPSE
RATES ABOVE IT. WE EXPECT SOME ELEVATED THUNDERSTORMS TO DEVELOP
THIS MORNING AS THE COLD FRONT AND UPPER LOW MOVE EAST. THE BEST
STORM CHANCES THIS MORNING WILL BE ACROSS THE NORTHERN HALF OF THE
REGION WHERE THE BEST LARGE SCALE FORCING WILL RESIDE. SINCE
ELEVATED INSTABILITY WILL REMAIN HIGH...ANY MORNING STORM THAT
DOES MANAGE TO FORM WILL HAVE A POTENTIAL TO PRODUCE LARGE HAIL.
THERE WILL BE A CHANCE OF SOME SURFACE BASED STORMS ACROSS THE
EASTERN PORTION OF NORTH TEXAS THIS AFTERNOON ALONG THE COLD FRONT
AS IT SLOWS DOWN. LARGE HAIL AND DAMAGING WINDS WILL BE POSSIBLE
WITH ANY OF THESE AFTERNOON STORMS. ALL STORMS SHOULD MOVE EAST OF
THE REGION THIS EVENING ONCE DRIER AIR FILTERS IN BEHIND THE COLD
FRONT.

THE PASSAGE OF THE COLD FRONT WILL TURN THE WIND TO THE
SOUTHWEST OR WEST AND INCREASE SPEEDS BETWEEN 20 AND 30 MPH ALONG
WITH SOME GUSTS NEAR 40 MPH...ESPECIALLY ACROSS THE WESTERN HALF
OF THE REGION. THEREFORE...WE WILL ISSUE A WIND ADVISORY GENERALLY
WEST OF THE INTERSTATE 35 CORRIDOR FROM 10 AM UNTIL 7 PM. WIND
SPEEDS ACROSS THE EASTERN HALF OF THE REGION SHOULD REMAIN JUST
BELOW ADVISORY CRITERIA.

ADIABATIC COMPRESSION/WARMING TODAY WILL RESULT IN AFTERNOON
HIGHS IN THE MIDDLE AND UPPER 80S AND EVEN SOME LOWER 90S IN THE
SOUTHWEST ZONES. THE HOT...WINDY AND DRY AIR WILL RESULT IN
ELEVATED FIRE WEATHER CONDITIONS ACROSS THE WESTERN HALF OF THE
REGION. HOWEVER...WE WILL NOT ISSUE A RED FLAG WARNING DUE TO
GREEN VEGETATION. WIND SPEEDS WILL DECREASE THIS EVENING AS THE
BOUNDARY LAYER DECOUPLES AND TEMPERATURES COOL INTO THE 50S
OVERNIGHT.

UPPER LEVEL NORTHWEST FLOW WILL PREVAIL ACROSS TEXAS THROUGH THE
UPCOMING WORK WEEK AS A HIGH AMPLITUDE RIDGE REMAINS ON THE WEST
COAST AND A DEEP TROUGH DOMINATES THE EASTERN HALF OF THE COUNTRY.
THIS PATTERN WILL KEEP NORTH TEXAS WEATHER DRY AND QUIET WITH
HIGHS MAINLY IN THE 70S TO LOWER 80S...AND LOWS IN THE UPPER 40S
AND 50S.

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&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  87  57  84  53  77 /  30   5   5  10   5
WACO, TX              89  55  86  52  81 /  20   5   5   5   5
PARIS, TX             84  57  80  52  76 /  50  20   5  10  10
DENTON, TX            87  51  84  49  79 /  30   5   5  10   5
MCKINNEY, TX          86  53  85  50  76 /  40  10   5  10   5
DALLAS, TX            86  61  86  55  79 /  30   5   5  10   5
TERRELL, TX           87  56  84  53  80 /  30  10   5  10  10
CORSICANA, TX         88  58  86  56  81 /  40  10   5  10  10
TEMPLE, TX            89  59  86  56  79 /  20   5   5   5   5
MINERAL WELLS, TX     88  51  87  50  78 /  20   5   5  10   5

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 7 PM CDT THIS EVENING
FOR TXZ091-092-100>103-115>118-129>133-141>144-156-157.

&&

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
330 AM CDT SUN APR 27 2014

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-281100-
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 SUN APR 27 2014

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...TODAY AND TONIGHT.
THERE IS A CHANCE OF THUNDERSTORMS ACROSS MUCH OF NORTH AND
CENTRAL TEXAS TODAY. THE THUNDERSTORM CHANCES WILL SHIFT EAST OF
THE I-35 CORRIDOR THIS AFTERNOON...THEN INTO EAST TEXAS THIS
EVENING...AS A PACIFIC FRONT MOVES THROUGH THE REGION. LARGE HAIL
AND DAMAGING WINDS WILL BE THE PRIMARY HAZARDS.

GUSTY SOUTHWEST WINDS BEHIND THE FRONT WILL USHER IN MUCH DRIER
AIR. WEST OF THE I-35 CORRIDOR...AFTERNOON TEMPERATURES WILL SOAR
INTO THE MID AND UPPER 80S...DROPPING RELATIVE HUMIDITY VALUES
BELOW 20 PERCENT. THE COMBINATION OF THE GUSTY WINDS AND LOW
HUMIDITY WILL RESULT IN A RISK OF GRASS FIRES...MAINLY ALONG AND
WEST OF A LINE FROM GAINESVILLE...TO FORT WORTH...TO GATESVILLE.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY.
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...
LIMITED SPOTTER ACTIVATION MAY BE REQUESTED TODAY...MAINLY EAST OF
THE I-35 CORRIDOR THIS AFTERNOON.

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