A nearly-stationary upper-level low positioned over western Texas created an environment conducive to three distinct severe weather episodes over eastern Texas. Monday morning's (3/12) fast-moving squall line was initiated from a shortwave rounding the base of the upper low.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS HGX wrote it up.
A nearly-stationary upper-level low positioned over western Texas created an environment conducive to three distinct severe weather episodes over eastern Texas. Monday morning's (3/12) fast-moving squall line was initiated from a shortwave rounding the base of the upper low. Tuesday's (3/13) scattered convection was a second shortwave riding up from the west southwest around the still quasi-stationary upper low. Wednesday's (3/14) events stemmed from the upper-low moving eastward over the region into Louisiana.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Houston/Galveston, TX wrote its last area forecast discussion before the first event at Mar 12, 2:10 AM CST, 15 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
310 AM CDT MON MAR 12 2007
.DISCUSSION...
LARGE MCS APPROACHING OUR WRN ZONES THIS HOUR WITH SOME ADDITIONAL
CONVECTIVE DEVELOPMENT OCCURRING AHEAD OF THE SYSTEM. STRENGTHING
DIFLUENCE ALOFT AND 30-35 KNOT LOW LEVEL JET WILL ENABLE THIS MCS
TO SUSTAIN ITSELF AND TRACK ACROSS THE ENTIRE CWA THIS MORNING.
LAPS DATA AND GFS/NAM FORECAST SOUNDINGS SHOW SIGNIFICANT LOW
LEVEL SHEAR IN PLACE WITH HELICITIES OF 150-250 M2/S2. WILL HAVE
A THREAT OF ISOLATED SEVERE STORMS MAINLY OVER THE SOUTHWEST HALF
OF THE CWA AS THE LINE OF STORMS CROSSES THE AREA. WILL KEEP
MENTION OF LOCALLY HEAVY RAINFALL FOR THIS MORNING. EXPECTING
WIDESPREAD RAINFALL AMOUNTS OF 1-2 INCHES...ISOLATED AMOUNTS UP
TO 3 INCHES ACROSS SE TX AS THIS FIRST MCS MOVES THROUGH. SOME
MINOR FLOODING PROBLEMS WILL BE POSSIBLE. HAVE HELD OFF ON ISSUING
A FLOOD WATCH AS MCS IS MOVING EASTWARD AT A FAIRLY GOOD CLIP
(ABOUT 25 KTS) AND SE TX HAS SEEN SUCH DRY WEATHER AS OF LATE.
ONCE THIS MCS CLEARS THE AREA...EXPECT TO SEE A BREAK IN THE
CONVECTIVE ACTIVITY FOR SEVERAL HOURS AS AIRMASS STABILIZES FOR
AWHILE. HAVE LOWERED POPS FOR THIS AFTN/EVENING ACCORDINGLY.
UPPER LOW WILL REMAIN NEARLY STATIONARY OVER SOUTHEASTERN NEW
MEXICO THEN BEGIN PUSHING SLOWLY EASTWARD ON TUESDAY. WILL SEE
CONTINUATION OF STRONG DIFLUENT FLOW ALOFT AND DEEP MOISTURE (PWS
1.5 INCHES+ AND 850 MB DEWPOINTS OF 10-12C) OVER SE TX THROUGH
MIDWEEK. EXPECT TO SEE ADDITIONAL CONVECTIVE COMPLEXES AFFECT SE
TX AS WEAK IMPULSES ROTATE AROUND THE MAIN UPPER LOW. EXPECT TO
SEE ANOTHER MCS FORM OVER SOUTH CENTRAL TEXAS THIS AFTN/EVENING...
TRACKING EAST INTO THE CWA LATE TONIGHT/TUESDAY. ADDITIONAL
CONVECTIVE COMPLEXES WILL AFFECT THE AREA TUE NIGHT/WEDNESDAY AS
UPPER LOW FINALLY PUSHES EAST ACROSS THE STATE. WILL SEE A
CONTINUED THREAT OF LOCALLY HEAVY RAINFALL THROUGH THE PERIOD.
ADDITIONAL RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE LIKELY TUESDAY
THROUGH WEDNESDAY WITH ISOLATED HIGHER TOTALS. MODEL FORECAST
SOUNDINGS DEPICT MUCH WEAKER SHEAR PROFILES FROM TONIGHT THROUGH
WEDNESDAY...SO SEVERE THREAT APPEARS VERY MARGINAL OVERALL.
STILL...A FEW ISOLATED SEVERE STORMS WILL BE POSSIBLE AS THE
CONVECTIVE COMPLEXES CROSS CWA.
MODELS SHOW SIGNIFICANT DRYING TAKING PLACE WED NIGHT/THURSDAY AS
UPPER LOW FINALLY PUSHES EAST OF THE AREA. A COLD FRONT IS
EXPECTED TO CROSS SE TX THU NIGHT...BUT HAVE REMOVED POPS WITH
MUCH DRIER AIRMASS IN PLACE. FRI/SAT WILL SEE NICE WEATHER WITH
JUST SOME CLOUD COVER AND COOLER TEMPS. MODELS SHOW RETURN FLOW
DEVELOPING SUNDAY AS SFC HIGH PUSHES EAST. WITH MOISTURE INCREASING
MOISTURE...AND HAVE ADDED LOW POPS FOR SUN NIGHT/MONDAY PERIOD.
HAVE MENTIONED SEA FOG FOR THIS MORNING IN THE GLS BAY AREA.
UNCERTAIN ON WHETHER OR NOT THE FOG WILL PERSIST PAST TODAY.
&&
.AVIATION...
MAIN CONCERN WILL BE MCS APPROACHING WESTERN PORTIONS OF CWFA EARLY
THIS MORNING. BAND OF THUNDERSTORMS EXTENDING FROM NEAR ROCKDALE TO
SCHULENBERG TO VICTORIA WITH CENTRAL PORTION OF LEADING EDGE SPEEDING
UP TO ABOUT 30-35 KTS. TAF SITES MAY GET GUSTY WINDS FROM STORMS AT
THIS BAND APPROACHES. MEANWHILE...LOW CEILINGS AND VISIBILITIES WITH
COPIOUS MOISTURE WILL HANG ON UNTIL MCS PASSES THROUGH. EXPECT CONDITIONS
TO IMPROVE AFTER MID MORNING.
&&
.MARINE...
TIGHTENING PRESSURE GRADIENT IN RESPONSE TO MCS HAS RESULTED IN SCEC
CONDITIONS FOR THE WATERS. EXPECT THIS TO PERSIST THROUGH MID TO LATE
MORNING WITH GRADIENT RELAXING SOMEWHAT BY MID DAY. MODERATE ONSHORE
FLOW WILL CONTINUE THROUGH WEDNESDAY. GFS CONTINUE TO INDICATE FRONT
MOVING THROUGH REGION THURSDAY NIGHT WITH A STRONG OFFSHORE FLOW DEVELOPING
EARLY FRIDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 73 63 72 62 74 / 100 70 70 60 50
HOUSTON (IAH) 71 64 72 63 74 / 100 60 70 60 60
GALVESTON (GLS) 71 64 71 63 72 / 100 60 70 60 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 10 AM CDT THIS MORNING
FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO
60 NM...WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL
OUT 20 NM...WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
&&
DISCUSSION...35
AVIATION/MARINE...37HAZARDOUS WEATHER OUTLOOK...UPDATED NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 1022 PM CDT SUN MAR 11 2007 TXZ163-164-176>179-195>200-210>214-226-227-235>238-130330- 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- 1022 PM CDT SUN MAR 11 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS. .DAY ONE...TONIGHT A LARGE AREA OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A VIGOROUS UPPER LEVEL STORM SYSTEM OVER WEST TEXAS IS EXPECTED TO MOVE INTO SOUTHEAST TEXAS OVERNIGHT. INCREASED LOW-LEVEL MOISTURE AND FAVORABLE WIND PROFILES INDICATE THE POSSIBILITY OF LOCALLY HEAVY RAINS AND ISOLATED SEVERE WEATHER WITH THESE STORMS AS THEY MOVE INTO THE REGION. OVERNIGHT RAINFALL AMOUNTS SHOULD AVERAGE FROM 1 TO 2 INCHES WITH ISOLATED AMOUNTS UP TO 4 INCHES POSSIBLE WHERE STORMS TRAIN. THE PRIMARY SEVERE WEATHER THREAT LOOKS TO BE HAIL AND STRONG DAMAGING WINDS. .DAYS TWO THROUGH THREE...MONDAY THROUGH TUESDAY SHOWERS AND THUNDERSTORMS ASSOCIATED WITH THE OVERNIGHT UPPER LEVEL DISTURBANCE WILL CONTINUE THROUGH THE FIRST HALF OF MONDAY. THE SLOW MOVEMENT OF THIS FEATURE WILL ALLOW THE THREAT OF HEAVY RAINS TO CONTINUE AS WELL. FOR THE REST OF THE PERIOD...ADDITIONAL DISTURBANCES WILL AFFECT THE AREA MONDAY NIGHT AND TUESDAY AS THE DEEP MOISTURE LINGERS. AT THIS TIME...THERE IS STILL QUITE A BIT OF UNCERTAINTY CONCERNING THE TIMING OF THESE FEATURES. HOWEVER IT APPEARS LIKELY THAT THE ENTIRE AREA WILL RECEIVE SIGNIFICANT RAINFALL. ADDITIONAL WIDESPREAD RAINFALL AMOUNTS OF 1 TO 3 INCHES ARE ANTICIPATED MONDAY...WITH ISOLATED 3 TO 5 INCHES AMOUNTS A POSSIBILITY. THIS COULD LEAD TO SOME FLOODING PROBLEMS THROUGH TUESDAY. .DAY FOUR...WEDNESDAY A STRONG UPPER LEVEL LOW WILL PUSH EAST ACROSS THE AREA ON WEDNESDAY. HEAVY RAINFALL AND ISOLATED SEVERE THUNDERSTORMS WILL AGAIN BE POSSIBLE. GRADUAL DRYING IS EXPECTED TO OCCUR WEDNESDAY NIGHT. .DAYS FIVE THROUGH SEVEN...THURSDAY THROUGH SATURDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS POSSIBLE MONDAY.
The Austin/San Antonio radar (KEWX), 121 km away, was scanning. The volume nearest the first event began at 08:22 UTC.
13 thunderstorm wind, 13 hail, 1 flash flood. Local standard time, as filed.
Approximately four homes received roof damage with debris in some homes. A baby was injured by flying glass when a tree fell into the baby's bedroom window. Minor structural damage to downtown businesses and trees.
Damage to several smaller shed structures with significant damage to one large shed-barn structure. Minor damage to a local ball park's grandstand metal roofing.
A couple of smaller trees down across road 6 miles NE of Bellville.
Couple of trees downed in and around Needville, one down on Violet Street and another at the SPJST Hall. Minor structural damage at Needville City Hall and tin roof damage to a business just north of Needville. Damage also reported to a rice dryer. A bank across Highway 36 received minor damage from the rice dryer's debris.
A barn roof blown off in Needville off of Paden Road.
Large tree down across a small residential porch structure.
Damage to large barn's metal roofing off of CR 434.
Quarter size hail at Interstate 10 and Studemont.
Quarter to tennis ball size hail between Lake Jackson and Sweeny.
Piper`s Crossing Apartments was damaged by straight line winds stripping a portion of a brick facade off. This brick facing damaged a few vehicles in the parking lot.
Residence damaged by near racqetball-size hail. Damage to home's front windows and screens with damage to 2 vehicles in yard. Roof damage to a city facility. 43 vehicle windshields were shattered with back windshield damage to 3 other vehicles at a local automotive dealership. Damage reported to two other businesses in the town of Brazoria with reports of damage to a few residential homes.
Nickel size hail at the Fry Road and Sun Glenn Blvd intersection.
Wind gust in the FM 1960 area near Houston International Airport.
Numerous cedar trees downed around home with a mobile trailer flipped over. Roof blown off a horse barn with minor damage to surrounding small structures off of Highway 60.
Penny size hail.
Nickel size hail.
Nickel size hail.
Numerous county-wide roads and some downtown Brenham streets were closed due to flooding. FM 1155 at New Years Creek and a portion of FM 2935 were closed due to high water. Some of these roadways were closed due to high water over them through Wednesday evening.
Quarter size hail.
Penny size hail.
Penny size hail.
Penny size hail.
Penny size hail.
Wind gust estimated at Reliant Stadium.
Penny size hail around the University of Houston and further south around Hobby Airport.
Tree down on one home with numerous downed tree limbs. National Weather Service in League City estimated wind gusts between 50 and 60 mph during the height of the storm.
Wind gust estimated in southeast Dickinson.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2007Every state in 2007This day in weather historyWarnings in Texas, March 2007
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 11237, 11259, 11238, 20940, 11240, 22241, 22240, 11241, 11242, 11267, 20941, 11269, 11243, 22242, 11244, 11245, 11246, 22244, 11247, 11248, 11249, 11250, 11252, 11276, 11253, 11254, 11255.