Alert archive / Texas / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 65, NWS Houston/Galveston, TX

April 4, 2012Brazoria County, Galveston County, Matagorda County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Apr 4, 2012, 3:30 PM CDT for Brazoria County, Galveston County, Matagorda County, Texas. It was in force for 45 min. 3 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 4, 2012, 3:30 PM CDT (20:30 UTC)
Expired: Apr 4, 2012, 4:15 PM CDT
In force: 45 min
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon

Counties Brazoria County, TX, Galveston County, TX, Matagorda County, TX

The radar

The Houston radar (KHGX), 55 km from the middle of the area, began a volume at 20:32 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Apr 4, 3:33 PM CDT	HAIL 0.25	Bay City, TX	PEA SIZE HAIL REPORTED AT FM457 AND HWY35 NEAR BAY CITY
Apr 4, 3:42 PM CDT	HAIL 0.5	Bay City, TX	TRAINED SPOTTER REPORTS HAIL INCREASED TO MARBLE SIZE AT FM457 AND HWY35
Apr 4, 3:46 PM CDT	HAIL 1	Bay City, TX	DIME TO QUARTER SIZE HAIL REPORTED BY TRAINED SPOTTER

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

Did it verify

Verified. The Iowa Environmental Mesonet's Cow matched one storm report to this severe thunderstorm warning; the first came 16 minutes after it went out.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 4, 12:55 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.5 hours before the alert went out and 238 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 355 J/kg
Mixed-layer CIN: -276 J/kg
Mixed-layer LCL: 762 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 24 m²/s²
0-3 km storm-relative helicity: 288 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -3.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

373 
WUUS54 KHGX 042030
SVRHGX
TXC039-167-321-042115-
/O.NEW.KHGX.SV.W.0065.120404T2030Z-120404T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
330 PM CDT WED APR 4 2012

THE NATIONAL WEATHER SERVICE IN LEAGUE CITY  HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  BRAZORIA COUNTY IN SOUTHEASTERN TEXAS...
  EXTREME SOUTHWESTERN GALVESTON COUNTY IN SOUTHEASTERN TEXAS...
  MATAGORDA COUNTY IN SOUTHEASTERN TEXAS...

* UNTIL 415 PM CDT

* AT 325 PM CDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 
  CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO GOLF BALL SIZE. 
  THIS STORM WAS LOCATED 8 MILES NORTHEAST OF OYSTER CREEK...OR 9 
  MILES NORTHEAST OF CLUTE...AND MOVING SOUTHEAST AT 15 MPH. OTHER 
  SEVERE STORMS STRETCH BACK TO THE WEST IN A LINE AND ARE CAPABLE 
  OF PRODUCING QUARTER INCH HAIL. 

* LOCATIONS IMPACTED INCLUDE...
  LAKE JACKSON...BAY CITY...ANGLETON...FREEPORT...CLUTE...SWEENY...
  RICHWOOD...BRAZORIA...WILD PEACH VILLAGE...JONES CREEK...
  VAN VLECK...OYSTER CREEK...MARKHAM...
  BAILEY'S PRAIRIE AND QUINTANA. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS IN EXCESS OF 60 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING AND VERY HEAVY RAIN. FOR YOUR 
PROTECTION...MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR 
HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE 
INTO AREAS WHERE WATER COVERS THE ROAD.

&&

LAT...LON 2876 9566 2874 9572 2898 9613 2925 9519
      2919 9508 2914 9508 2916 9502 2909 9511
      2913 9508 2921 9514 2911 9517 2907 9512
      2902 9520 2911 9518 2911 9519 2901 9523
      2886 9539 2873 9569
TIME...MOT...LOC 2022Z 308DEG 15KT 2911 9526 

$$

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Apr 4, 1:04 PM CDT, 2 hours 26 minutes earlier.

Area forecast discussion, Apr 4, 1:04 PM CDT, 2 hours 26 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
104 PM CDT WED APR 4 2012

.AVIATION...
DEALING WITH SHRA/+TSRA RIGHT NOW BETWEEN HOU AND GALVESTON.
SCT/BKN MVFR CEILINGS POSSIBLE AREA WIDE THIS AFTERNOON WITH
VCSH/VCTS SOUTH OF THE IAH AREA. EXPECT TO SEE THE DEVELOPMENT OF
MVFR/IFR CEILINGS AND VISIBILITIES OVERNIGHT...MAINLY SOUTH OF THE
I-10 AREA...DUE TO LIGHT WINDS AND WET GROUNDS. SKIES SHOULD CLEAR
OUT AS THE DAY PROGRESSES TOMORROW WITH DRIER WEST WINDS.  42
&&

.PREV DISCUSSION... /ISSUED 1124 AM CDT WED APR 4 2012/

UPDATE...
MORNING FORECAST UPDATE.

DISCUSSION...
IN THE SHORT TERM LOOKING TO KEEP HIGH CHANCE POPS IN THE FORECAST
FOR WIDELY SCT STORMS. STORMS COULD BE ON THE STRONG SIDE AND
APPROACH SEVERE LEVELS. SMALL HAIL IN A FEW STRONG STORMS COULD BE
POSSIBLE WITH BRIEF HEAVY RAINFALL. LOOKS LIKE UPPER LEVEL LOW
OVER OK WILL MOVE EAST WITH TROUGH AXIS FINALLY PUSHING THROUGH
TONIGHT. MAY NEED TO HAVE SOME POPS IN THE FORECAST THROUGH
MIDNIGHT BUT WILL EVAULATE THAT WITH SHORT RANGE GUIDANCE.
OTHERWISE EXPECT DRIER CONDITIONS FOR THE END OF THE WEEK AS UPPER
LEVEL RIDGE BUILDS OVER TX AND PLAINS.

FINAL NOTE...NWS HOUSTON/GALVESTON HAS STARTED AN OPERATIONAL TEST
OF AWIPS2 THROUGH FRIDAY.

39

PREV DISCUSSION... /ISSUED 429 AM CDT WED APR 4 2012/

DISCUSSION...
THE COMBINATION OF A WEAK FRONT MOVING EASTWARD AND AN OUTFLOW
BOUNDARY MOVING SOUTHWARD BROUGHT STRONG TO SEVERE THUNDERSTORMS
ACROSS THE NORTHERN PORTIONS OF SE TX EARLIER TONIGHT. ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE THIS MORNING
AHEAD OF THE WEAKENING COLD FRONT. THE GFS LOOKS REASONABLE IN
SLOWING THE EASTWARD PROGRESSION OF THE BOUNDARY THIS MORNING AND
THEN KEEPING CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS OVER
THE SOUTHEASTERN THIRD OF THE FORECAST AREA THIS AFTERNOON.

FOR THE REMAINDER OF THE FORECAST...THE GFS AND ECMWF HAD SIMILAR
SOLUTIONS. AN UPPER LEVEL RIDGE WILL THEN BUILD OVER THE AREA
BEGINNING ON THURSDAY. THIS WILL BRING WARMER AND DRIER CONDITIONS
ACROSS SE TX THROUGH THE WEEKEND. EARLY NEXT WEEK THE FLOW PATTERN
ALOFT BECOMES MORE NORTHWESTERLY AS AN UPPER LEVEL TROUGH FORMS
OVER THE NORTHEASTERN PART OF THE COUNTRY. THIS FLOW PATTERN
SHOULD HELP DRIVE A BACK DOOR COLD FRONT INTO SE TX. WILL
INTRODUCE ISOLATED RAIN CHANCES AHEAD OF THE FRONT ON TUESDAY.

MARINE...
LIGHT WIND REGIME WILL BE IN PLACE FOR A FEW DAYS. SOUTHERLY WINDS
SHOULD BECOME MORE VARIABLE AS THE OUTFLOW BOUNDARY OVER SETX
MOVES INTO THE COASTAL AREAS THIS MORNING. WEAK HIGH PRESSURE
WILL DEPART FOLLOWED BY A PACIFIC FRONT THAT SAGS DOWN OVER THE
COASTAL WATERS LATE THURSDAY. EAST AND SOUTHEAST FLOW OF 5 TO 15
KNOTS SHOULD PREVAIL FRIDAY THROUGH THE WEEKEND. TIDES AROUND 1
FOOT ABOVE NORMAL SHOULD CONTINUE TO DAY THEN SLOWLY LOWER
THURSDAY BEFORE RETURNING TO AROUND 1 FOOT ABOVE NORMAL WITH THE
EAST AND SOUTHEAST FETCH.

45

&&

.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL)      74  56  76  55  77 /  10  10  10  10  10
HOUSTON (IAH)              74  56  76  57  77 /  20  10  10  10  10
GALVESTON (GLS)            73  62  75  64  74 /  30  10  10  10  10

&&

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

DISCUSSION...39
AVIATION/MARINE...42

Hazardous weather outlook, Apr 4, 11:40 AM CDT, 3 hours 50 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1140 AM CDT WED APR 4 2012

GMZ330-335-350-355-TXZ163-164-176>179-195>200-210>214-226-227-
235>238-051645-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GALVESTON BAY-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-
MADISON-MATAGORDA-MATAGORDA BAY-MONTGOMERY-POLK-SAN JACINTO-
TRINITY-WALKER-WALLER-WASHINGTON-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM-
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM-WHARTON-
1140 AM CDT WED APR 4 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT

A FEW ISOLATED TO SCATTERED STRONG THUNDERSTORMS ARE EXPECTED
MAINLY SOUTH OF INTERSTATE 10 TODAY AND THIS EVENING. SOME STORMS
COULD BECOME SEVERE WITH HAIL AND GUSTY WINDS. THE ACTIVITY SHOULD
REMAIN ALONG THE COAST AND PUSH EAST THROUGH THE AFTERNOON. BRIEF
HEAVY RAINFALL WILL ALSO BE POSSIBLE WITH SOME OF THE STRONGER
STORMS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON.

In the hours before

Local storm report, Apr 4, 1:27 PM CDT, 2 hours 3 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
127 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0122 PM     HEAVY RAIN       ALVIN                   29.43N 95.25W
04/04/2012  E0.00 INCH       BRAZORIA           TX   EMERGENCY MNGR

            0.5 INCH RAIN FELL IN 10 MINUTES REPORTED BY BRAZORIA
            COUNTY EM IN THE PAST HOUR

&&

TWG

Local storm report, Apr 4, 1:33 PM CDT, 1 hour 57 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
133 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0130 PM     HAIL             DICKINSON               29.45N 95.07W
04/04/2012  E0.25 INCH       GALVESTON          TX   COUNTY OFFICIAL

            PEA SIZE HAIL REPORTED BY PUBLIC SAFETY OFFICIAL AT FM517
            AND HWY 646

&&

TWG

Local storm report, Apr 4, 1:36 PM CDT, 1 hour 54 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
136 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0121 PM     HAIL             LEAGUE CITY             29.49N 95.11W
04/04/2012  E0.25 INCH       GALVESTON          TX   PUBLIC

            PEA SIZE HAIL REPORTED IN WEST PART OF LEAGUE CITY

&&

TWG

Local storm report, Apr 4, 1:49 PM CDT, 1 hour 41 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
149 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1238 PM     HAIL             ALVIN                   29.43N 95.25W
04/04/2012  E2.75 INCH       BRAZORIA           TX   PUBLIC

            BASEBALL SIZE HAIL REPORTED ON COMMUNITY DRIVE NEAR ALVIN
            COMMUNITY COLLEGE

&&

TWG

Local storm report, Apr 4, 2:15 PM CDT, 1 hour 15 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
215 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0212 PM     HAIL             HITCHCOCK               29.32N 95.02W
04/04/2012  E0.25 INCH       GALVESTON          TX   LAW ENFORCEMENT

            PEA SIZE HAIL REPORTED BY LAW ENFORCEMENT

&&

TWG

Local storm report, Apr 4, 3:04 PM CDT, 26 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
304 PM CDT WED APR 04 2012

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0255 PM     HAIL             LAKE JACKSON            29.04N 95.45W
04/04/2012  E1.00 INCH       BRAZORIA           TX   PUBLIC

            LAW ENFORCEMENT RELAYED REPORTED OF QUARTER SIZE HAIL BY
            THE PUBLIC

&&

TWG

The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 3, 7:15 PM CDT	Special Weather Statement	HGX	Brazos, Burleson	60 min
Apr 3, 8:00 PM CDT	Special Weather Statement	HGX	Houston, Madison	60 min
Apr 3, 8:09 PM CDT	Special Weather Statement	HGX	Brazos, Burleson, Washington	81 min
Apr 3, 8:51 PM CDT	Severe Thunderstorm Warning	HGX	Houston	39 min
Apr 3, 9:12 PM CDT	Severe Thunderstorm Warning	HGX	Brazos, Grimes, Madison	48 min
Apr 3, 9:28 PM CDT	Severe Thunderstorm Warning	HGX	Houston	47 min
Apr 3, 9:57 PM CDT	Severe Thunderstorm Warning	HGX	Brazos, Grimes, Madison, Walker	48 min
Apr 3, 10:14 PM CDT	Areal Flood Advisory	HGX	Houston, Madison	2 hr
Apr 3, 10:48 PM CDT	Special Weather Statement	HGX	Houston	57 min
Apr 3, 10:50 PM CDT	Special Weather Statement	HGX	Madison	55 min
Apr 3, 11:35 PM CDT	Special Weather Statement	HGX	Trinity	55 min
Apr 3, 11:53 PM CDT	Special Weather Statement	HGX	Walker	52 min
Apr 4, 12:29 AM CDT	Severe Thunderstorm Warning	HGX	Polk, Trinity	46 min
Apr 4, 12:34 AM CDT	Special Weather Statement	HGX	Montgomery	56 min
Apr 4, 12:44 AM CDT	Severe Thunderstorm Warning	HGX	Montgomery, Walker	46 min
Apr 4, 1:32 AM CDT	Special Weather Statement	HGX	Montgomery, San Jacinto	58 min
Apr 4, 1:52 AM CDT	Severe Thunderstorm Warning	HGX	Montgomery, San Jacinto, Walker	38 min
Apr 4, 2:31 AM CDT	Severe Thunderstorm Warning	HGX	Liberty, Polk, San Jacinto	59 min
Apr 4, 8:49 AM CDT	Special Marine Warning	HGX		56 min
Apr 4, 11:09 AM CDT	Special Weather Statement	HGX	Harris	51 min
Apr 4, 11:37 AM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Fort Bend, Harris	38 min
Apr 4, 12:17 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Fort Bend, Galveston, Harris	43 min
Apr 4, 12:59 PM CDT	Areal Flood Advisory	HGX	Brazoria, Fort Bend, Galveston	61 min
Apr 4, 1:02 PM CDT	Tornado Warning	HGX	Brazoria, Galveston	43 min
Apr 4, 1:20 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria	40 min
Apr 4, 1:35 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Galveston	40 min
Apr 4, 1:43 PM CDT	Special Marine Warning	HGX		92 min
Apr 4, 1:59 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Matagorda	46 min
Apr 4, 2:12 PM CDT	Severe Thunderstorm Warning	HGX	Galveston	25 min
Apr 4, 2:17 PM CDT	Special Marine Warning	HGX		88 min
Apr 4, 2:42 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Matagorda	48 min
Apr 4, 3:00 PM CDT	Special Marine Warning	HGX		90 min
Apr 4, 3:23 PM CDT	Severe Thunderstorm Warning	HGX	Jackson, Matagorda	52 min
Apr 4, 3:35 PM CDT	Areal Flood Advisory	HGX	Brazoria, Matagorda	115 min
Apr 4, 3:46 PM CDT	Special Marine Warning	HGX		89 min
Apr 4, 4:13 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Jackson, Matagorda	62 min
Apr 4, 4:23 PM CDT	Special Marine Warning	HGX		82 min
Apr 4, 4:51 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Fort Bend, Jackson, Matagorda, Wharton	54 min
Apr 4, 5:07 PM CDT	Severe Thunderstorm Warning	HGX	Jackson, Matagorda, Wharton	53 min
Apr 4, 5:22 PM CDT	Areal Flood Advisory	HGX	Brazoria, Fort Bend, Jackson, Matagorda, Wharton	80 min
Apr 4, 5:29 PM CDT	Special Marine Warning	HGX		91 min
Apr 4, 5:41 PM CDT	Special Marine Warning	HGX		32 min
Apr 4, 5:54 PM CDT	Special Weather Statement	HGX	Fort Bend	51 min
Apr 4, 6:27 PM CDT	Special Marine Warning	HGX		93 min

Nearby

Severe Thunderstorm Warnings in Texas, 2012 Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.