Alert archive / Texas / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 71, NWS Houston/Galveston, TX

April 27, 1997Brazoria County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Apr 27, 1997, 3:50 AM CDT for Brazoria County, Texas. It was in force for 25 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 27, 1997, 3:50 AM CDT (08:50 UTC)
Expired
Apr 27, 1997, 4:15 AM CDT
In force
25 min
Issued by
NWS Houston/Galveston, TX
Area
Whole counties

County Brazoria County, TX

The radar

The Houston radar (KHGX), 48 km from the middle of the area, began a volume at 08:52 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.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 8.8 hours before the alert went out and 240 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-pSkew-T log-p diagram, Lake Charles Mun, LA at 00:00Z on 1997-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 73 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 00:00Z on 1997-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
73 J/kg
Mixed-layer CIN
-281 J/kg
Mixed-layer LCL
600 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
180 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

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

384 
WUUS1 KHOU 270851 RRA
SVRHOU
TXC039-270915-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
350 AM CDT SUN APR 27 1997
 
THE NATIONAL WEATHER SERVICE IN HOUSTON/GALVESTON HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  415 AM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTHEAST TEXAS
 
   ...BRAZORIA COUNTY
 
AT 345 AM..RADAR INDICATED SEVERE THUNDERSTORM NEAR ANGLETON. THIS
STORM IS MOVING TO THE NORTH NORTHEAST AT 30 MPH. ALVIN IS IN THE PATH
OF THIS STORM.
 
THIS IS A DANGEROUS STORM.  IF YOU ARE IN ITS PATH...PREPARE
FOR DAMAGING WIND IN EXCESS OF 55 MPH...LARGE HAIL...AND
VERY HEAVY RAIN.  IF CAUGHT OUTSIDE... MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT STAY AWAY FROM WINDOWS.

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 27, 3:32 AM CDT, 18 minutes earlier.

Area forecast discussion, Apr 27, 3:32 AM CDT, 18 minutes before
SOUTHEAST TEXAS FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
232 AM CDT SUN APR 27 1997

UPPER LOW TO THE SW BEGINNING TO MOVE TOWARD TX.  SPEED MAX CURRENTLY
MOVING TO THE N THROUGH TX ASSISTING SVR TSTM DEVELOPMENT.  LARGE
HAIL HAS BEEN REPORTED WITH A VIL FOR THIS CELL RIGHT AROUND 50.
MORE STORMS TO THE S ARE MOVING N TOWARD HOUSTON AREA.  SO FAR...NO
FLOODING PROBLEMS ANYWHERE.  MODELS SHOW MOST SIGNIFICANT UVV VALUES
FROM LA EASTWARD WHERE THETA-E RIDGE SHIFTS TO DURING THIS FORECAST.
UNCERTAIN AS TO HOW MUCH RAIN WILL DEVELOP WITH THE CURRENT ACTIVITY
MOVING THIS WAY FROM THE S.  WITH UPPER LOW STILL PROGGED TO MOVE
RIGHT ACROSS SE TX...ELEVATED STORMS STILL CAPABLE OF DUMPING SOME
LOCALLY HEAVY RAINS.  WOULD THEREFORE LIKE TO KEEP THE FLASH FLOOD
WATCH UP FOR THIS MORNING FOR ALL OF SE TX AND MENTION LOCALLY HEAVY
RAINS IN THE ZONES.  COASTAL FLOOD WARNING WILL NOT NEED TO BE
REISSUED.  WINDS HAVE BEEN FROM THE N TO NW FOR A WHILE NOW...AND
TIDE READINGS FROM THE HOUSTON/GALVESTON PORTS SYSTEM ARE DOWN TO
1.50 TO 2 FEET ABOVE NORMAL.  EXPECT THESE READINGS TO CONTINUE TO
DECREASE.  WILL COVER SITUATION WITH AN MWSHOU.

MOISTURE VALUES BEGIN TO DECREASE AFTER 36 HOURS (12Z MONDAY MORNING)
AS LOW PRESSURE NEAR THE ARKLATEX CONTINUES TO MOVE OFF TO THE E.
WILL CALL FOR SKIES TO BECOME PARTLY CLOUDY ON MONDAY AND WILL BRING
RAIN CHANCES DOWN TO ZERO.  DRY COUPLE OF DAYS TO FOLLOW AFTER MONDAY.

PRELIM DETAILS ARE NEXT.

     FLASH FLOOD WATCH THIS MORNING
     LOCALLY HEAVY RAIN POSSIBLE TODAY

CLL T/C BECOMING B/V 63/51 76 51  6400
IAH T/C BECOMING B/V 66/55 76 52  7400
GLS T/C BECOMING B/V 67/62 74 60  7400

42

In the hours before

Special weather statement, Apr 27, 12:15 AM CDT, 3 hours 35 minutes before
TXZ211-237-210-227-198-213-163-200-511-236-199-179-178-164-177-
212-197-226-196-195-214-238-235-176-271115-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1217 AM CDT SUN APR 27 1997

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
ALL OF SOUTHEAST TEXAS UNTIL 600 AM THIS SUNDAY MORNING. THIS WATCH
INCLUDES AUSTIN...BRAZORIA...BRAZOSCHAMBERS...COLOTADO...FORT BEND...
GALVESTON...GRIMES...HARRIS...HOUSTON...MONTGOMERY...POLK...SAN JACINTO.
TRINITY...WALKER...WALLER...WASTHIGTON...WHARTON...JACKSON...
MATAGORDA COUNTIES.

A SEVERE THUNDERSTORM WATCH MEANS SEVERE THUNDERSTORMS ARE POSSIBLE IN
AND NEAR THE WATCH AREA.
Special weather statement, Apr 27, 12:17 AM CDT, 3 hours 33 minutes before
TXZ211-237-210-227-198-213-163-200-511-236-199-179-178-164-177-
212-197-226-196-195-214-238-235-176-271115-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
1217 AM CDT SUN APR 27 1997

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR
ALL OF SOUTHEAST TEXAS UNTIL 600 AM THIS SUNDAY MORNING. THIS WATCH
INCLUDES AUSTIN...BRAZORIA...BRAZOSCHAMBERS...COLOTADO...FORT BEND...
GALVESTON...GRIMES...HARRIS...HOUSTON...MONTGOMERY...POLK...SAN JACINTO.
TRINITY...WALKER...WALLER...WASTHIGTON...WHARTON...JACKSON...
MATAGORDA COUNTIES.

A SEVERE THUNDERSTORM WATCH MEANS SEVERE THUNDERSTORMS ARE POSSIBLE IN
AND NEAR THE WATCH AREA.

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 26, 11:03 PM CDTSevere Thunderstorm WarningHGXAustin, Colorado57 min
Apr 26, 11:31 PM CDTSevere Thunderstorm WarningHGXWashington59 min
Apr 26, 11:52 PM CDTSevere Thunderstorm WarningHGXWaller38 min
Apr 27, 12:02 AM CDTSevere Thunderstorm WarningHGXGrimes, Montgomery58 min
Apr 27, 12:45 AM CDTSevere Thunderstorm WarningHGXWalker60 min
Apr 27, 1:03 AM CDTSevere Thunderstorm WarningHGXSan Jacinto57 min
Apr 27, 1:20 AM CDTSevere Thunderstorm WarningHGXPolk55 min
Apr 27, 2:00 AM CDTSevere Thunderstorm WarningHGXTrinity45 min
Apr 27, 4:09 AM CDTSevere Thunderstorm WarningHGXGalveston66 min
Apr 27, 4:21 AM CDTSevere Thunderstorm WarningHGXHarris54 min
Apr 27, 5:06 AM CDTSevere Thunderstorm WarningHGXLiberty69 min
Apr 27, 5:37 AM CDTSevere Thunderstorm WarningHGXBrazoria53 min
Apr 27, 8:16 AM CDTSevere Thunderstorm WarningHGXBrazoria64 min
Apr 27, 8:49 AM CDTSevere Thunderstorm WarningHGXHarris56 min
Apr 27, 9:17 AM CDTSevere Thunderstorm WarningHGXHarris, Liberty58 min

Nearby

Severe Thunderstorm Warnings in Texas, 1997Every severe thunderstorm warning in 1997

Sources

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