Hail and Damaging Winds in Texas, June 28, 2011

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
650 PM CDT TUE JUN 28 2011

.AVIATION...
CONCERNS:  NONE AT THE TAF SITES.

CONVECTIVE COMPLEX ACROSS SOUTHEAST OKLAHOMA AND NORTHEAST TEXAS
WILL CONTINUE THROUGH THE EVENING HOURS AND MAY STILL BE ON GOING
INTO THE LATE NIGHT HOURS. THE ONLY AFFECT ON THE METROPLEX TAF
SITES COULD BE AN OUTFLOW BOUNDARY THAT PROPAGATES WEST-
SOUTHWESTWARD AND MIGHT REACH KDAL AND KDFW WITH A WIND SHIFT.
WILL AWAIT NEXT UPDATE 03Z OR THE 06Z ROUTINE TO COVER THIS IF IT
DEVELOPS.

OTHERWISE...VFR CIGS/VIS WITH DIURNAL SHIFTING SOUTHERLY FLOW
6-12KTS TONIGHT AND 7-15KTS ON WEDNESDAY. 75

&&

.PREV DISCUSSION... /ISSUED 342 PM CDT TUE JUN 28 2011/
TWO AREAS OF INTEREST FOR POSSIBLE CONVECTION LATER THIS AFTERNOON
AND EVENING...ALTHOUGH CHANCES ARE LOW IN EITHER CASE. THE BEST
CHANCES FOR THUNDERSTORM DEVELOPMENT ARE IN OUR NORTHEAST ZONES
WHERE THE BEST MOISTURE CONVERGENCE AND SURFACE BASED INSTABILITY
EXIST. ADDITIONALLY...OUTFLOW FROM THE COMPLEX OF THUNDERSTORMS
PUSHING SOUTH THROUGH ARKANSAS INTO NORTHERN LOUISIANA MAY ACT AS
AN IMPETUS FOR THUNDERSTORM INITIATION. SURFACE OBSERVATIONS
INDICATE A TONGUE OF MOISTURE ALONG A PARIS TO MCKINNEY TO MINERAL
WELLS LINE...LIKELY ALONG AN OLD OUTFLOW BOUNDARY FROM THIS
MORNINGS CONVECTION THROUGH OKLAHOMA. BOTH OF THESE AREAS WILL BE
MONITORED FOR POTENTIAL CONVECTIVE INITIATION. CONFIDENCE IN THE
TIMING/LOCATION OF ISOLATED THUNDERSTORM DEVELOPMENT IN THESE
AREAS IS LOW BUT ANY STORM THAT DOES DEVELOP WILL BE IN A
FAVORABLE ENVIRONMENT TO PRODUCE STRONG DOWNBURST WINDS.

MODELS CONTINUE TO PROG NW MOVEMENT OF THE UPPER LEVEL RIDGE ON
WEDNESDAY ALLOWING THE POTENTIAL FOR ISOLATED THUNDERSTORMS IN OUR
EASTERN ZONES. OTHERWISE...TEMPERATURES AROUND 100 FOR THE ENTIRE
CWA WITH MOSTLY SUNNY SKIES. AN UPPER LEVEL DISTURBANCE MOVES
THROUGH THE CENTRAL PLAINS ON THURSDAY AND RESULTS IN AN INCREASE
OF SOUTHERLY WINDS ACROSS THE CWA. THIS SHOULD ALLOW FOR MORE
MIXING AND THURSDAY STILL APPEARS TO BE THE WARMEST DAY THIS
WEEK...ALTHOUGH ONLY BY A DEGREE OR TWO. TROPICAL SYSTEM IN THE
BAY OF CAMPECHE IS STILL PROGGED TO MOVE INTO MEXICO SOMETIME
THURSDAY. EVEN WITH THE UPPER RIDGE MOVING NORTHWEST...MOST OF THE
MOISTURE ASSOCIATED WITH THIS SYSTEM WILL REMAIN WELL SOUTH OF
NORTH TEXAS.

BEGINNING SATURDAY DIURNALLY DRIVEN CONVECTION LOOKS POSSIBLE.
SOUTHERLY FLOW THROUGH 500 MB WILL ALLOW MORE MOISTURE AND LESS
CAPPING THROUGHOUT NORTH TEXAS. ADDITIONALLY...THE UPPER LEVEL
RIDGE BEGINS TO DEVELOP A WEAKNESS SATURDAY. THEREFORE...DAYTIME
HEATING SHOULD BE ENOUGH TO DESTABILIZE THE ATMOSPHERE AND
GENERATE AIRMASS THUNDERSTORMS. AS A RESULT...INTRODUCED ISOLATED
THUNDERSTORMS DURING EACH AFTERNOON SATURDAY THROUGH MONDAY. GFS
GUIDANCE HAS A 20 POP FOR THIS SAME TIME FRAME BUT KEPT 10 POPS AT
THIS TIME. WILL INCREASE IN FUTURE FORECASTS IF MODELS SHOW
CONSISTENCY.

AN ADDITIONAL FORECAST ITEM THAT IS WORTH MENTIONING IN REGARDS TO
THE WEAKENING RIDGE. IT APPEARS THIS WEAKENING IS A RESULT OF A TUTT
LOW THAT MOVES WESTWARD ALONG THE GULF COAST BEGINNING FRIDAY
MORNING. THIS FEATURE DEVELOPS ALONG A SHEAR AXIS RESULTING FROM A
WASHED OUT FRONTAL BOUNDARY. BOTH THE ECMWF AND GFS DEVELOP THIS
LOW...ALTHOUGH THE TIMING AND PROGRESSION BETWEEN THE TWO DIFFER
SIGNIFICANTLY. ELECTED TO NOT INCREASE POPS ON MONDAY OR INTRODUCE
POPS ON TUESDAY SINCE THE UNCERTAINTY ASSOCIATED WITH THE TUTTS FORECAST
IS HIGH. HOWEVER...THIS FEATURE WILL NEED TO BE MONITORED CLOSELY
IN FUTURE MODEL RUNS AS IT COULD HAVE A SIGNIFICANT IMPACT ON OUR
WEATHER NEXT WEEK.

42/MM

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  78 100  78 101  78 /   5   5   5   5   5
WACO, TX              76 102  75 102  75 /   0   5   5   5   5
PARIS, TX             75  99  76  99  76 /  20  10  10  10  10
DENTON, TX            74 101  74 100  74 /   5   5   5   5   5
MCKINNEY, TX          73  98  74  98  73 /  10   5   5   5   5
DALLAS, TX            79 100  79 100  79 /   5   5   5   5   5
TERRELL, TX           75  98  75  98  75 /  10  10  10  10  10
CORSICANA, TX         75  98  76  97  75 /   5   5   5  10  10
TEMPLE, TX            74 100  74 101  73 /   0   5   5   5   5
MINERAL WELLS, TX     73 104  73 103  73 /   5   0   0   0   0

&&

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

&&

75/

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE FORT WORTH TX
251 PM CDT TUE JUN 28 2011

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-291200-
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-
251 PM CDT TUE JUN 28 2011

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...THROUGH TONIGHT.

THERE IS A SLIGHT CHANCE OF STRONG TO SEVERE THUNDERSTORMS
NORTHEAST OF A BOWIE...TO DENTON...TO DALLAS...TO CANTON LINE
THROUGH THIS EVENING. DAMAGING WINDS...FREQUENT LIGHTNING...AND
POSSIBLY HAIL CAN BE EXPECTED WITH STORMS THAT DO OCCUR.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY.

ISOLATED THUNDERSTORMS ARE POSSIBLE WEDNESDAY AFTERNOON AND
EVENING EAST OF A SHERMAN...ROCKWALL...MEXIA LINE. ANY STORMS
COULD BECOME BRIEFLY STRONG OR MARGINALLY SEVERE WITH DOWNBURST
WINDS AND FREQUENT LIGHTNING.

ISOLATED AFTERNOON AND EVENING THUNDERSTORMS WILL BE POSSIBLE EACH
DAY THIS WEEKEND AND ON THE FOURTH OF JULY ACROSS THE EASTERN HALF
OF NORTH TEXAS.

.SPOTTER INFORMATION STATEMENT...
LIMITED SPOTTER ACTIVATION MAY BE REQUESTED NORTHEAST OF A BOWIE...
TO DENTON...TO DALLAS...TO CANTON LINE THROUGH THIS EVENING.

05/