Severe Thunderstorm Warning 151, NWS Fort Worth, TX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
958 PM CDT TUE MAY 2 2006

.958 PM PUBLIC DISCUSSION...
TWO SQUALL LINES WILL CONTINUE TO MOVE EAST ACROSS NORTH TEXAS. WE
HAVE UPDATED THE ZONE FORECAST AND UPPED POPS IN MOST AREAS TO 60
PERCENT. DAMAGING WINDS AND HAIL OF PENNY TO QUARTER SIZE APPEAR TO
BE THE MAIN THREATS.  #26

.AVIATION...
PER REASONS DISCUSSED BELOW...HAVE INCLUDED THUNDER AT METROPLEX
SITES FROM 4-9Z AND WACO FROM 6-11Z.  MVFR STRATUS POSSIBLE IN WACO
BEFORE STORMS MOVE IN...BUT HAVE LEFT IT OUT OF METROPLEX DUE TO
POSSIBLE STORM OUTFLOW.  WILL CONTINUE TO SHOW VFR WED MORNING
THROUGH 0Z...WITH AFTERNOON AIRMASS STABILIZED BY TONIGHT/S ROUND.
OBVIOUSLY WILL CONTINUE TO CLOSELY MONITOR THE CONVECTIVE TRENDS TO
THE NW...AND AMENDMENTS MAY BE FORTHCOMING.  TR.92

&&

.620 PM DISCUSSION...
WE AGREE WITH THE PREVIOUS ASSESSMENT THAT TONIGHTS FORECAST IS ONE
OF CONSIDERABLE DIFFICULTY.

OUR CURRENT THINKING IS THIS...
THE NORTH-SOUTH AREA OF NUMEROUS SEVERE THUNDERSTORMS...FROM THE
EASTERN OKLAHOMA PANHANDLE...SOUTHWARD TO NORTH OF SAN ANGELO...WILL
CONTINUE TO MOVE SLOWLY EAST OVER THE NEXT FEW HOURS. THEN...AFTER
THE SUN SETS...A LOW LEVEL JET STREAM (LLJ) WILL FORM NEAR AN AXIS
FROM NEAR COMANCHE...NORTHWARD TO CHILDRESS AND THE OKLAHOMA/TEXAS
PANHANDLE BORDER.

BY MID- TO LATE EVENING...THE SEVERE STORMS NOW IN THE PANHANDLE
PROBABLY WILL COALESCE INTO A MESOSCALE CLUSTER OF STRONG TO SEVERE
STORMS...CALLED A MESOSCALE CONVECTIVE COMPLEX (MCS)...IN RESPONSE
TO A FAVORABLE SUPPLY OF MOISTURE AND CONVERGENCE PROVIDED BY THE
NORTHWARD DIRECTED NOCTURNAL LLJ. THE MCS WILL THEN TURN MORE
SOUTHERLY (AS STORMS FORM SOUTHWARD BECAUSE OF THE STRONG INFLOW OF
ELEVATED WARM...MOIST AIR ASSOCIATED WITH THE LLJ)...TRACKING INTO
THE FACE OF THE LLJ...AND DROPPING ALMOST DUE SOUTH ACROSS WESTERN
PORTIONS OF NORTH TEXAS AND ADJACENT PORTIONS OF WEST TEXAS...(THE
LOW LEVEL CONVERGENCE IS DUE TO THE LLJ...WHICH WILL BE AUGMENTED
IN THE GENERATION OF NEW STORMS FURTHER SOUTH WITH TIME...BY THE
FACT THAT THE LEFT OVER BOUNDARY FROM LAST NIGHTS STORMS IS IN THE
SAME AREA.)

60% CONFIDENCE IS FAIRLY HIGH...BUT LEAVES ROOM FOR OTHER POSSIBLE
CONVECTIVE EVOLUTIONS.)

AT THIS TIME...WE WILL UPDATE THE HAZARDOUS WEATHER OUTLOOK AND THE
ZONE FORECAST...TO INCREASE THE THREAT OF THUNDERSTORMS...MAINLY IN
THE WESTERN COUNTIES OF NORTH TEXAS. WE WILL LOWER POPS IN THE NORTH
AND EAST A BIT...WHILE INCREASING THEM IN THE WEST.   #26

&&

400 PM .DISCUSSION...
VERY DIFFICULT FORECAST THIS AFTERNOON...AS SEVERAL THINGS ARE
CURRENTLY AFFECTING THE ATMOSPHERE. MORNING MCS HAS LEFT OUTFLOW
BOUNDARIES ACROSS OUR SRN SECTIONS AND ACROSS SRN AND CENTRAL OK
THIS AFTERNOON. DESPITE ABUNDANT CAPE ACROSS OUR SOUTH...STORMS
HAVE HAD A DIFFICULT TIME DEVELOPING. THIS IS LIKELY DUE TO LARGE
SCALE UPPER LEVEL SUBSIDENCE AS INDICATED BY H7-H3 DIV-Q LAYER.
MORNING CONVECTION HAS ALSO STABILIZED THE N TEXAS AREA
SOMEWHAT...AS INDICATED BY 18Z KFWS SOUNDING. CAN NOT RULE OUT
STORMS GETTING GOING JUST ABOUT ANYWHERE IN OUR CWA LATE THIS
AFTERNOON AND EVENING...BUT MODELS AND PAST EXPERIENCE SUGGEST WE
WILL HAVE TO WAIT UNTIL LATER THIS EVENING/OVERNIGHT FOR THE
SUBSIDENCE TO WEAKEN AND THE NEXT WEAK H5 VORT MAX TO ARRIVE.
STORMS SHOULD GET GOING ACROSS WRN OK AND THE ERN TX
PANHANDLE...BEFORE MOVING E-NE INTO N TEXAS LATER TONIGHT.
FORECAST CAPE AND INSTABILITY SHOULD BE ENOUGH TO GET SOME LARGE
HAIL AND DAMAGING WINDS. WL GO ALONG WITH SPC OUTLOOK AREA.

STORMS MAY LINGER INTO THE MORNING HOURS...AS A DECAYING MCS.
OTHERWISE...SUBSIDENCE FROM EXITING PVA AND INCREASED H5 RIDGING
SHOULD TURN OFF THE RAIN FOR MUCH OF WED. NEXT FRONT AND UPPER
LEVEL SYSTEM APPROACH LATE WEDNESDAY NIGHT INTO THUR...WITH FROPA
EXPECTED ON FRIDAY. STILL LOOKS LIKE A DECENT SHOT AT ADDITIONAL
STORMS...WITH SEVERE WX NOT OUT OF THE QUESTION. WEEKEND LOOKS
GOOD...WITH NEXT CHANCE OF RAIN MONDAY.

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  67  88  66  86 /  30  20  30  30
WACO, TX              67  89  66  87 /  20  10   0  10
PARIS, TX             66  86  65  84 /  40  20  40  40
DENTON, TX            67  87  66  85 /  40  20  40  30
MCKINNEY, TX          66  85  65  84 /  40  20  40  30
DALLAS, TX            67  87  65  86 /  30  20  30  30
TERRELL, TX           66  86  65  85 /  30  20  20  20
CORSICANA, TX         67  87  65  87 /  20  10  10  20
TEMPLE, TX            67  88  66  87 /  20  10   0  10

&&

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

/80

HAZARDOUS WEATHER OUTLOOK FOR NORTH TEXAS...CORRECTED
NATIONAL WEATHER SERVICE FORT WORTH TX
850 PM CDT TUE MAY 2 2006

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-031100-
ANDERSON-BELL-BOSQUE-COLLIN-COMANCHE-COOKE-CORYELL-DALLAS-DELTA-
DENTON-EASTLAND-ELLIS-ERATH-FALLS-FANNIN-FREESTONE-GRAYSON-HAMILTON-
HENDERSON-HILL-HOOD-HOPKINS-HUNT-JACK-JOHNSON-KAUFMAN-LAMAR-LAMPASAS-
LEON-LIMESTONE-MCLENNAN-MILAM-MILLS-MONTAGUE-NAVARRO-PALO PINTO-
PARKER-RAINS-ROBERTSON-ROCKWALL-SOMERVELL-STEPHENS-TARRANT-VAN ZANDT-
WISE-YOUNG-
710 PM CDT TUE MAY 2 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...
THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS TONIGHT ACROSS ALL OF
NORTH TEXAS. LARGE HAIL...DAMAGING WINDS...AND LOCALLY HEAVY RAIN
WILL BE THE MAIN WEATHER THREATS.

SEVERAL LINES OF THUNDERSTORMS WILL MOVE EAST AND SOUTHEAST ACROSS
NORTH TEXAS TONIGHT. THE STRONGEST STORMS WILL BE CAPABLE OF
PRODUCING GOLF BALL SIZE HAIL AND 60 TO 70 MPH WINDS.

.DAYS TWO THROUGH SEVEN...
THERE IS A CHANCE OF THUNDERSTORMS ACROSS THE NORTHERN HALF OF NORTH
TEXAS WEDNESDAY THROUGH THURSDAY AND ACROSS THE ENTIRE REGION
THURSDAY NIGHT THROUGH SATURDAY MORNING. SEVERE THUNDERSTORMS ARE
POSSIBLE ACROSS THE NORTHERN HALF OF THE REGION WEDNESDAY AND
THURSDAY AND REGION-WIDE FRIDAY.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION LIKELY WILL BE REQUESTED LATE THIS EVENING AND
OVERNIGHT...MAINLY NEAR AND WEST OF INTERSTATE 35.

26

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
912 PM CDT TUE MAY 2 2006

TXZ116>118-129>132-141-030245-

COMANCHE-EASTLAND-ERATH-HOOD-PALO PINTO-PARKER-SOMERVELL-TARRANT-
912 PM CDT TUE MAY 2 2006

...SIGNIFICANT WEATHER UPDATE...

AT 912 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 9 MILES NORTHEAST OF
MINERAL WELLS TO 13 MILES NORTHWEST OF COMANCHE...MOVING EAST AT 20
MPH.

CITIES IN THE PATH OF THESE STORMS INCLUDE ALEDO...ANNETTA...AZLE...
BLUFF DALE...BRIAR...CHALK MOUNTAIN...CLAIRETTE...COOL...DE LEON...
DUBLIN...EAGLE MOUNTAIN...GLEN ROSE...GORDON...GORMAN...GRANBURY...
HUCKABAY...HUDSON OAKS...LAKESIDE...LINGLEVILLE...LIPAN...MINERAL
WELLS...MORGAN MILL...OAK TRAIL SHORES...PECAN ACRES...PELICAN BAY...
PURVES...RENO...SALESVILLE...SPRINGTOWN...STEPHENVILLE...
WEATHERFORD...WHITE SETTLEMENT...WILLOW PARK...DINOSAUR VALLEY STATE
PARK AND MINERAL WELLS STATE PARK.

PEA-SIZED HAIL...WIND GUSTS TO 50 MPH...AND HEAVY RAIN CAN BE
EXPECTED FROM THESE STORMS.

IF THESE STORMS INTENSIFY...ONE OR MORE SEVERE THUNDERSTORM WARNINGS
MAY BE NEEDED.

13

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
923 PM CDT TUE MAY 2 2006

TXZ100-101-030300-

JACK-YOUNG-
923 PM CDT TUE MAY 2 2006

...SIGNIFICANT WEATHER UPDATE...

AT 923 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A SEVERE
THUNDERSTORM 11 MILES NORTH OF OLNEY...MOVING SOUTHEAST AT 25 MPH.

CITIES IN THE PATH OF THIS STORM INCLUDE GRAHAM...JEAN...JERMYN...
LOVING AND OLNEY.

IF THIS STORM CONTINUES ON ITS PRESENT COURSE...A SEVERE WEATHER
WARNING MAY BE NEEDED FOR YOUNG AND POSSIBLY JACK COUNTIES PRIOR TO
10 PM.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
937 PM CDT TUE MAY 2 2006

TXZ091-030300-

MONTAGUE-
937 PM CDT TUE MAY 2 2006

...SIGNIFICANT WEATHER UPDATE...

AT 937 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
STRONG THUNDERSTORM 12 MILES SOUTHEAST OF HENRIETTA...MOVING EAST AT
30 MPH.

CITIES IN THE PATH OF THIS STORM INCLUDE MONTAGUE...NOCONA...
RINGGOLD...ST. JO AND STONEBURG.

SMALL HAIL UP TO ONE-HALF INCH IN DIAMETER AND WIND GUSTS TO 50 MPH
CAN BE EXPECTED FROM THIS STORM.

IF THIS STORM INTENSIFIES...A SEVERE WEATHER WARNING MAY BE NEEDED.