Tornado Warning 11, NWS Brownsville, TX

000 
WWUS54 KBRO 201840
SVSBRO

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE BROWNSVILLE TX
138 PM CDT THU JUL 20 2006

TXC061-489-201848-
/O.CAN.KBRO.TO.W.0011.000000T0000Z-060720T1900Z/
WILLACY TX-CAMERON TX-
138 PM CDT THU JUL 20 2006

...THE TORNADO WARNING FOR NORTHWESTERN CAMERON AND SOUTH CENTRAL
WILLACY COUNTIES IS CANCELLED...

THE THUNDERSTORM THAT PRODUCED A WEAK TORNADO NEAR SEBASTIAN AND 
HIGHWAY 77 HAS WEAKEN. THE STORM IS LOCATED WEST OF HIGHWAY 77 ABOUT 
2 MILES SOUTHWEST OF LYFORD. EXPECT HEAVY RAIN...GUSTY WINDS AND 
FREQUENT CLOUD TO GROUND LIGHTNING WITH THIS THUNDERSTORM AS IT 
MOVES NORTHWEST AT 5 TO 10 MPH. 

LAT...LON 2625 9786 2634 9763 2647 9776 2644 9787

$$

GB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BROWNSVILLE TX
1000 AM CDT THU JUL 20 2006

.DISCUSSION...AN UPPER TROUGH EXTENDS WEST FROM THE ATLANTIC OCEAN
AND ACROSS THE CENTRAL GULF OF MEXICO TO A LOW HEIGHT CENTER ABOVE
SOUTH TEXAS. PARTLY AS A RESULT OF THIS FEATURE...AND PARTLY DUE TO
ABUNDANT LOW LEVEL TROPICAL MOISTURE ADVECTING TOWARD THE AREA FROM
THE SOUTH...SCATTERED SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS
ARE ONGOING OVER THE COASTAL WATERS THIS MORNING. FOR THE MOST
PART...THIS CONVECTION IS REMAINING OFFSHORE...HOWEVER ONCE DAYTIME
HEATING INCREASES...CONVECTION MAY ENCROACH INTO THE COASTAL
COUNTIES AS IT DID YESTERDAY. THE MORNING SOUNDING SHOWS SUFFICIENT
INSTABILITY AND MOISTURE FOR MODERATE THUNDERSTORM DEVELOPMENT THIS
AFTERNOON...WITH THE LIKELIHOOD OF LOCALLY HEAVY RAINFALL. THIS IS
CURRENTLY COVERED ADEQUATELY BY THE INHERITED FORECAST.

THE ABOVE SITUATION SHOULD PERSIST THROUGH THIS WEEKEND...AFTER
WHICH CONDITIONS WILL CHANGE SOMEWHAT AS MIDLEVEL TROUGHING BECOMES
MORE SIGNIFICANT OVER THE MISSISSIPPI VALLEY AND NORTHWEST GULF.
NEXT MONDAY...THE MODELS HINT AT CHANCE POPS DUE TO INSTABILITY
MOVING UP FROM THE BAY OF CAMPECHE...PERHAPS IN CONJUNCTION WITH THE
FORMATION OF A SURFACE TROUGH ALONG THE EAST MEXICAN COAST. AT THE
SAME TIME...HIGH PRESSURE LOOKS TO BUILD STRONGLY INTO THE GULF...
ENHANCING ONSHORE FLOW.
&&

.MARINE...AT 8AM...BUOY 42040 REPORTED SE WINDS AT 5 KNOTS WITH SEAS
OF 2 FEET. NO SIGNIFICANT CHANGE TO THE FORECAST EXPECTED...WITH
LIGHT TO MODERATE SOUTHEAST WINDS AND LOW SEAS PERSISTING THROUGH
THE WEEKEND. SURFACE HIGH PRESSURE EXTENDING WEST ACROSS THE GULF
WILL MAINTAIN TRANQUIL WEATHER. SHOWERS AND THUNDERSTORMS COULD
BECOME MORE SCATTERED TODAY AS AN UPPER TROUGH EXTEND ALONG THE
COASTAL WATERS AND INTO THE GULF. THE TROUGH WEAKENS FRIDAY AND
SATURDAY ALLOW FOR ONLY A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS. THEN ANOTHER INCREASE IN RAIN ACTIVITY IS POSSIBLE
FOR SUNDAY AND EARLY NEXT WEEK AS FRONTAL TROUGH MOVES SOUTH ACROSS
THE GULF COAST.
&&

.AVIATION...VFR WILL BE THE PRIMARY CONDITION ACROSS THE RIO GRANDE
VALLEY TODAY AND FRIDAY. SHOWERS AND THUNDERSTORMS COULD BECOME
SCATTERED LATER TODAY WITH PERIODS OF MVFR AND BRIEF IFR CONDITIONS
WITH THE STORMS. LOWER VISIBILITIES AND OBSCURATIONS WILL BE DUE TO
HEAVY RAINFALL WITH CEILINGS LOWERING TEMPORARILY.
&&

.PREV DISCUSSION...ISSUED AT 215 AM CDT THU JUL 20 2006...TROPICAL
MOISTURE OVER THE REGION WILL ALLOW FOR ISOLD CONVECTION TODAY AS
SEA BREEZE MOVES INLAND INTERACTING WITH OUTFLOW BOUNDARIES FROM A
DISSIPATING MCS MVG INTO SE TX THIS AM. UPPER LEVEL RIDGE WILL
CONTINUE TO BUILD WEST BECOMING CENTERED OVER THE FOUR CORNERS
REGION BY LATE FRI/EARLY SAT AS AN UPPER TROUGH DIGS INTO THE
MIDWEST. MINOR SHORT WAVES WILL ROTATE AROUND THE RIDGE PRODUCING
SCHC POPS THROUGH SUN. MODELS INDICATE AN UPPER LOW WILL DIG INTO
THE SRN PLAINS MON WITH A WEAK FRONT MOVING INTO AND STALLING OVER
SOUTH CENTRAL TEXAS POOLING MOISTURE OVER THE REGION. THIS WILL
COMBINE WITH MID LEVEL DISTURBANCES MOVING NW OUT OF THE BAY OF
CAMPECHE TO INCREASE POPS TO CHC CATEGORY.
&&

.PRELIMINARY POINT TEMPS/POPS...
BAYVIEW/PORT ISABEL  91  79  91  78  91 /  20  10  20  10  20
BROWNSVILLE          94  76  95  76  95 /  20  10  20  10  10
HARLINGEN            97  75  97  76  97 /  20  10  20  10  10
MCALLEN              98  76  98  76  99 /  20  10  10  10  10
RIO GRANDE CITY     100  76 100  76 100 /  10  20  10  10  10
SOUTH PADRE ISLAND   90  79  90  79  91 /  20  10  20  10  20
&&

.BRO WATCHES/WARNINGS/ADVISORIES...NONE.
&&

54/69/MARTINEZ

THIS PRODUCT IS ALSO AVAILABLE ON OUR INTERNET WEB PAGE AT:
HTTP://WWW.SRH.NOAA.GOV/BRO

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BROWNSVILLE TX
407 AM CDT THU JUL 20 2006

TXZ248>257-211030-
ZAPATA-JIM HOGG-BROOKS-KENEDY-STARR-HIDALGO-INLAND WILLACY-
INLAND CAMERON-COASTAL WILLACY-COASTAL CAMERON-
407 AM CDT THU JUL 20 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF DEEP SOUTH
TEXAS.

.DAY ONE...TODAY AND TONIGHT

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER
DEEP SOUTH TEXAS ON THURSDAY. TEMPORARY PONDING OF WATER ON
ROADWAYS AND IN LOW-LYING AREAS IS POSSIBLE WITH THIS ACTIVITY. NO
OTHER HAZARDOUS WEATHER IS ANTICIPATED THROUGH THE PERIOD.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED OVER
DEEP SOUTH TEXAS THROUGH THE PERIOD. TEMPORARY PONDING OF WATER ON
ROADWAYS AND IN LOW-LYING AREAS IS POSSIBLE WITH THIS ACTIVITY. NO
OTHER HAZARDOUS WEATHER IS ANTICIPATED THROUGH THE PERIOD.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED.