Damaging Winds in Texas, August 6, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
408 AM CDT SUN AUG 6 2006

.DISCUSSION...
THE UPPER LOW WILL AFFECT SE TX OVER THE NEXT COUPLE OF DAYS
BEFORE THE HIGH PRESSURE AREA REASSERTS ITSELF OVER THE LATTER
HALF OF THE WEEK. EARLY THIS MORNING THE LOW WAS LOCATED NEAR THE
SE LA COAST. THE GFS AND NAM HANDLED THE SYSTEM A BIT DIFFERENTLY
AND THE NAM LOOKED UNREALISTIC IN DEVELOPING A SURFACE LOW IN THE
GULF IN MOVING IT ONSHORE AND IN ITS AGGRESSIVE HANDLING OF THE
REMNANTS OF CHRIS DURING THE MID WEEK PERIOD. LIKED THE GFS WITH
THE HIGHER PW/S THOUGH LIKE THE NAM IT MAY HAVE THE UPPER LOW A
BIT TOO FAR SOUTH THIS MORNING.

WITH THAT IN MIND...THE MAIN FORECAST ITEM OF CONCERN FOR TODAY
AND MONDAY WILL BE RAINFALL COVERAGE AND AMOUNTS. LOCALLY HEAVY
RAINFALL IS POSSIBLE DUE TO FORECASTED PW/S NEAR 2.3 AND THE
PRESENCE OF DIFFLUENT FLOW ALOFT. (A PW OF 2.3 IS ABOUT 2 STANDARD
DEVIATIONS ABOVE NORMAL FOR BOTH LCH AND CRP FOR THE FIRST PART OF
AUGUST.) WILL HAVE TO SEE HOW THINGS EVOLVE WITH THE UPPER LOW AND
IN THE THE MODEL RUNS LATER TODAY AS TO CONTINUING THE MENTION OF
LOCALLY HEAVY RAINFALL FOR MONDAY. THE COVERAGE SHOULD BECOME AT
LEAST 60 PERCENT BY MIDDAY TODAY AFTER THE CONVECTIVE TEMPERATURE
IS REACHED. THE FAR NORTHERN COUNTIES MAY SEE A BIT LESS
COVERAGE BECAUSE OF THE POSITIONING OF THE UPPER LOW. THERE WAS
MORE UNCERTAINTY ON MONDAY FOR COVERAGE AND AMOUNTS.

WILL MENTION THE POSSIBILITY OF SEVERE STORMS TODAY. THE COLDER
TEMPERATURES ALOFT AND THE POSITIONING OF THE UPPER LOW MAY HELP
PROVIDE THE POTENTIAL FOR WET MICROBURSTS. SEE THE SPC DISCUSSION
AND THE HAZARDOUS WEATHER OUTLOOK FOR MORE DETAILS.

TUESDAY SHOULD SEE EVEN LESS COVERAGE AS THE UPPER LOW DISSIPATES
AND THE HIGH PRESSURE ALOFT BEGINS MOVING TOWARD AR...NORTHERN
LA...AND EASTERN TX. ONLY EXPECT THE SEA BREEZE TO PROVIDE ANY
RAINFALL AFTER WEDNESDAY. TEMPERATURES SHOULD BE MUCH LOWER
TODAY AND MONDAY DUE TO CLOUD COVER. A RETURN TO THE HEAT OF THE
PAST FEW DAYS WILL OCCUR BY WEDNESDAY.

40

&&

.AVIATION...
MCS OVER LOUISIANA HAS SHIFTED WEST OVER SE TX AND IS IN THE
PROCESS OF DECAYING. WITH CONVECTIVE TEMPS IN THE MID/UPPER 80S
AND AN OUTFLOW BOUNDARY LYING ACROSS THE REGION...THINK TSRA WILL
REDEVELOP LATER THIS MORNING OR EARLY AFTERNOON. AGREE WITH SPC
REASONING REGARDING WET MICROBURSTS AND WILL TEMPO VRB25KT AT AREA
TAF SITES. 43

&&

.MARINE...
E-NE SFC FLOW WILL DEVELOP IN THE WAKE OF AN OUTFLOW BOUNDARY
MOVING ACROSS THE WATERS OVERNIGHT. AM EXPECTING THE FLOW TO
BECOME SE BY AFTERNOON. WIND SPEED/DIRECTION WILL BE MORE
DEPENDENT ON CONVECTION THAN THE ACTUAL WEAK PRESSURE GRADIENT IN
PLACE. WILL ADD WIND AND SEAS HIGHER IN AND NEAR TSRA AS MULTI-
CELL STORMS COULD ORGANIZE AND PRODUCE SOME HIGHER WIND GUSTS. GWW
STILL ADVERTISING SOME HIGHER THAN EXPECTED SEA HEIGHTS BY
TUESDAY. WILL MAINTAIN CURRENT FORECAST REGARDING SEAS FOR
TUESDAY. 43

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      94  74  91  74  96 /  50  30  50  30  20
HOUSTON (IAH)              91  75  89  75  93 /  70  40  60  30  30
GALVESTON (GLS)            88  79  87  79  89 /  70  50  60  30  30

&&

.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.

&&

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1006 PM CDT SAT AUG 5 2006

TXZ163-164-176>179-195>200-210>214-226-227-235>238-061200-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
1006 PM CDT SAT AUG 5 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...REST OF TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS...SOME STORMS POSSIBLY STRONG
TO SEVERE...WILL MOVE INTO EASTERN PORTIONS OF SOUTHEAST TEXAS LATE
THIS EVENING INTO EARLY SUNDAY MORNING. EXPECT HEAVY RAINFALL AND
FREQUENT CLOUD TO GROUND LIGHTNING AS WELL WINDS GUSTS TO NEAR 50
MPH WITH THESE THUNDERSTORMS. IN ADDITION...SOME STORMS MAY
PRODUCE SMALL SIZE HAIL.

.DAYS TWO AND THREE...SUNDAY AND MONDAY

AN UPPER LEVEL LOW PRESSURE SYSTEM WILL RESULT IN SCATTERED
TO NUMEROUS SHOWERS AND THUNDERSTORMS. SOME OF THE THUNDERSTORMS
WILL BE CAPABLE OF PRODUCING BRIEF HEAVY RAINFALL. RAINFALL
AMOUNTS OF ONE HALF INCH TO AN INCH ARE EXPECTED. ISOLATED AMOUNTS
OF 2 TO 3 INCHES ARE POSSIBLE.

.DAYS FOUR THROUGH SEVEN...TUESDAY THROUGH FRIDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATE TONIGHT.