Tornado and Flash Flooding in Texas, April 28, 2009

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
943 AM CDT TUE APR 28 2009

.UPDATE...
A QUICK UPDATE WAS DONE TO INCREASE POPS AND QPF ACROSS THE
SOUTHEASTERN ZONES. AN COMPLEX OF SHOWERS AND THUNDERSTORMS WILL
CONTINUE TO MOVE ACROSS THE SOUTH CENTRAL AND SOUTHEASTERN ZONES
THIS MORNING...AND WILL PRODUCE LOCALIZED FLOODING. THUS HAVE
ALSO ADDED HEAVY RAIN WORDING TO THE ZONES. SOME LOCATIONS WILL
PICK UP 2 TO 5 INCHES OF RAIN WITH THESE STORMS.

VISIBILITIES FROM THE FOG ARE INCREASING...AND WE MAY CANCEL THE
DENSE FOG ADVISORY AFTER LOOKING AT THE 10 AM OBSERVATIONS.

58

&&

.AVIATION...
/12Z UPDATE/

WEAK COLD FRONT MOVING THROUGH NORTH TEXAS THIS MORNING WILL
CONTINUE TO SLOW BEFORE STALLING ACROSS THE REGION OVER THE NEXT
FEW HOURS. VLIFR CONDS HAVE DEVELOPED ALONG THE LEADING EDGE OF
THE FRONT WITH 1/4SM FG VV001 BEING REPORTED AT THE METROPLEX
TERMINALS. THINK THESE CONDS WILL CONTINUE THRU ABOUT 14Z BEFORE
DISPERSING A BIT. WILL MAINTAIN IFR CONDS FOR OVC009 THROUGH MID
MORNING. FARTHER TO THE SOUTH...AN AREA OF SHOWERS AND
THUNDERSTORMS CONTINUES TO MOVE TO THE NORTH...CURRENTLY AFFECTING
THE WACO AREA. AREA OF RAIN AND STORMS WILL CONTINUE TO MOVE NORTH
INTO THE METROPLEX AFTER 15Z AND WILL TEMPO -TSRA THROUGH MIDDAY.
MVFR CONDS EXPECTED BY EARLY AFTN WITH BKN025 CIGS...WHICH MAY
LIFT TO BKN040 BY LATE AFTN. ABUNDANT MOISTURE PERSISTS OVERNIGHT
AND WITH INCREASING LLJ AFTER DARK...EXPECT IFR CONDS ONCE AGAIN TONIGHT.

91/DUNN

&&

.PREV UPDATE...
.UPDATE...
THE COLD FRONT HAS SLOWED DOWN THIS MORNING AND AS A RESULT THE
FOG IS LINGERING ACROSS THE CENTRAL PORTIONS OF THE FORECAST AREA
A LITTLE LONGER THAN EARLIER EXPECTED. WE HAVE DECIDED TO ISSUE A
QUICK DENSE FOG ADVISORY MAINLY ACROSS THE METROPLEX AND AREAS
EAST AND WEST. ALL VISIBILITIES SHOULD IMPROVE BY 11 AM.

79

&&

.PREV DISCUSSION... /ISSUED 307 AM CDT TUE APR 28 2009/

A SHORT WAVE WILL ROTATE ACROSS THE EXTREME SOUTHERN SECTIONS OF
NORTH TEXAS THIS MORNING AND BRING SCATTERED TO NUMEROUS SHOWERS
AND THUNDERSTORMS. ACTIVITY SHOULD BE ENHANCED AFTER SUNRISE ONCE
A WEAK COLD FRONT MOVES INTO THAT REGION AND PROVIDES ADDITIONAL
LIFT. SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. HOWEVER...THE
SEVERE POTENTIAL SHOULD BE LOW. THE REMAINDER OF NORTH TEXAS MAY
SEE A FEW SHOWERS AND THUNDERSTORMS TODAY BUT ANY STORMS THAT FORM
SHOULD BE ELEVATED.

NORTH TEXAS WILL REMAIN IN WEST TO SOUTHWEST FLOW ALOFT THROUGH
THE WEEKEND WITH STORM CHANCES MAINLY DRIVEN BY THE PASSAGE OF
BRIEF SHORT WAVE ENERGY. ONE SHORT WAVE WILL MOVE ACROSS THE
REGION WEDNESDAY AND BRING SCATTERED STORMS...ESPECIALLY TO THE
NORTHWEST ZONES. ANOTHER WAVE AND ASSOCIATED COLD FRONT WILL MOVE
ACROSS THE NORTHERN ZONES FRIDAY NIGHT AND BRING ANOTHER CHANCE OF
STORMS THROUGH SATURDAY. A FINAL SHORT WAVE IS PROGGED TO MOVE
ACROSS THE REGION SUNDAY/SUNDAY NIGHT WITH MORE STORMS POSSIBLE.

CLOUDS AND LOW LEVEL MOISTURE WILL BE ABUNDANT FOR MUCH OF THE
WEEK AND THAT SHOULD KEEP AFTERNOON HIGHS MAINLY IN THE MIDDLE 70S TO
LOWER 80S. LOW TEMPERATURES WILL BE MAINLY IN THE 60S...EXCEPT FOR
SOME UPPER 50S THIS MORNING AND AGAIN ON THE WEEKEND.

79

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  77  67  80  67  83 /  30  10  30  20  10
WACO, TX              77  67  80  68  83 /  70  20  20  20  10
PARIS, TX             74  65  79  65  81 /  40  20  30  20  20
DENTON, TX            76  66  80  67  82 /  20  20  30  20  10
MCKINNEY, TX          76  65  79  67  81 /  30  10  30  20  10
DALLAS, TX            78  69  79  68  83 /  40  10  30  20  10
TERRELL, TX           77  66  80  67  82 /  50  10  30  20  10
CORSICANA, TX         77  66  80  67  82 /  80  10  20  20  10
TEMPLE, TX            79  67  80  68  81 /  60  20  20  20  10

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
DENSE FOG ADVISORY UNTIL 11 AM CDT THIS MORNING FOR TXZ094-095-
104>107-116>123-129>134-141>145.

&&

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HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
740 AM CDT TUE APR 28 2009

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-291100-
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-
740 AM CDT TUE APR 28 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...TODAY AND TONIGHT.

PATCHY DENSE FOG WILL REDUCE VISIBILITIES TO LESS THAN 1/4 MILE AT
TIMES THROUGH THE MORNING ACROSS THE CENTRAL PORTIONS OF NORTH
TEXAS. THEREFORE...A DENSE FOG ADVISORY IS IN EFFECT UNTIL 11 AM.

SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS MOST OF NORTH TEXAS
THROUGH THE DAY. THE STRONGEST STORMS WILL BE CAPABLE OF PRODUCING
SMALL HAIL AND WIND GUSTS TO 50 MPH. FREQUENT LIGHTNING AND
LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE THROUGH THE AFTERNOON.

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

THUNDERSTORM CHANCES WILL CONTINUE ACROSS NORTH TEXAS WEDNESDAY
THROUGH SUNDAY AS SEVERAL UPPER LEVEL DISTURBANCES MOVE THROUGH
THE PLAINS. THERE IS A SLIGHT RISK FOR SEVERE THUNDERSTORMS
WEDNESDAY AFTERNOON MAINLY ALONG AND WEST OF INTERSTATE 35. LARGE
HAIL AND DAMAGING WINDS WILL BE THE MAIN THREATS ON WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...
VERY LIMITED SPOTTER ACTIVATION MAY BE REQUESTED TODAY WITH THE
STRONGEST STORMS.

DUNN