Alert archive / Texas / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 61, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this severe thunderstorm warning at Apr 17, 2009, 11:51 PM CDT for Liberty County, Texas. It was in force for 39 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 17, 2009, 11:51 PM CDT (04:51 UTC)
- Expired
- Apr 18, 2009, 12:30 AM CDT
- In force
- 39 min
- Issued by
- NWS Houston/Galveston, TX
- Area
- Storm-based polygon
County Liberty County, TX
The radar
The Houston radar (KHGX), 80 km from the middle of the area, began a volume at 04:51 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
Corpus Christi, TX (KCRP), launched 00:00Z, 4.9 hours before the alert went out and 365 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.
- Mixed-layer CAPE
- 3044 J/kg
- Mixed-layer CIN
- -54 J/kg
- Mixed-layer LCL
- 729 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- -22 m²/s²
- 0-3 km storm-relative helicity
- -85 m²/s²
- Significant tornado parameter
- -0.6
- Supercell composite
- -2.3
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 17, 10:20 PM CDT, 1 hour 31 minutes earlier.
Area forecast discussion, Apr 17, 10:20 PM CDT, 1 hour 31 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Hazardous weather outlook, Apr 17, 2:12 PM CDT, 9 hours 39 minutes before
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 212 PM CDT FRI APR 17 2009 GMZ330-335-350-355-370-375-TXZ163-164-176>179-195>200-210>214-226- 227-235>238-181200- 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 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-WHARTON- 212 PM CDT FRI APR 17 2009 ...SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS SOUTHEAST TEXAS THROUGH SATURDAY EVENING... ...FLOOD WATCH IN EFFECT FOR ALL OF SOUTHEAST TEXAS THROUGH SATURDAY EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS. .DAY ONE...THIS AFTERNOON AND TONIGHT DISTURBANCES ROTATING AROUND A STRONG STORM SYSTEM WILL CONTINUE TO SUPPORT THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF SOUTHEAST TEXAS. SOME OF THE STRONGER STORMS MAY BECOME SEVERE AND COULD PRODUCE STRONG DAMAGING WINDS...LARGE HAIL AND ISOLATED TORNADOES. IN ADDITION TO THE SEVERE WEATHER THREAT...VERY HIGH MOISTURE LEVELS WILL PERSIST ACROSS MUCH OF THE AREA AND WILL SUPPORT THE THREAT FOR LOCALLY HEAVY RAINFALL. FLOODING OF STREETS...FEEDER ROADS...SECONDARY ROADS...LOW WATER CROSSINGS...AND AREA CREEKS AND RIVERS WILL BE POSSIBLE WHERE TRAINING OF STORMS OCCURS. .DAY TWO...SATURDAY THROUGH SATURDAY NIGHT DISTURBANCES ROTATING AROUND A STRONG STORM SYSTEM WILL CONTINUE TO SUPPORT THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS PORTIONS OF SOUTHEAST TEXAS. SOME OF THE STRONGER STORMS MAY BECOME SEVERE AND COULD PRODUCE STRONG DAMAGING WINDS...LARGE HAIL AND ISOLATED TORNADOES. IN ADDITION TO THE SEVERE WEATHER THREAT...VERY HIGH MOISTURE LEVELS WILL PERSIST ACROSS MUCH OF THE AREA AND WILL SUPPORT THE THREAT FOR LOCALLY HEAVY RAINFALL. FLOODING OF STREETS...FEEDER ROADS...SECONDARY ROADS...LOW WATER CROSSINGS...AND AREA CREEKS AND RIVERS WILL BE POSSIBLE WHERE TRAINING OF STORMS OCCURS. RAINFALL TOTALS FOR TODAY AND SATURDAY ARE EXPECTED TO AVERAGE 2 TO 4 INCHES. WHERE HEAVY RAINFALL HAS ALREADY OCCURRED...ISOLATED TWO DAY TOTALS OF 15 TO 20 INCHES ARE POSSIBLE...ESPECIALLY ACROSS PORTIONS OF NORTHWEST COLORADO COUNTY AND NORTHERN AUSTIN COUNTY. THE THREAT FOR THE HEAVIEST RAINFALL IS EXPECTED GENERALLY ALONG AND NORTH OF THE U.S. HIGHWAY 59 CORRIDOR...GENERALLY ALONG AND NORTH OF A LINE FROM EDNA TO RICHMOND TO HOUSTON TO CLEVELAND TO CORRIGAN. A COLD FRONT WILL CROSS THE AREA LATE SATURDAY NIGHT ENDING THE RAIN CHANCES AND SEVERE WEATHER THREAT ACTIVITY SHIFTS TO THE EAST OF THE AREA. .DAYS THREE THROUGH SEVEN...SUNDAY THROUGH THURSDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED AT ANY TIME THROUGH SATURDAY EVENING.
In the hours before
Local storm report, Apr 17, 7:31 PM CDT, 4 hours 20 minutes before
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 17, 9:25 PM CDT | River Flood Warning | HGX | Jackson, Lavaca | 3 days |
| Apr 17, 9:25 PM CDT | River Flood Warning | HGX | Jackson, Lavaca | 4 days |
| Apr 17, 9:25 PM CDT | River Flood Warning | HGX | Jackson | 5 days |
| Apr 18, 2:37 AM CDT | Severe Thunderstorm Warning | HGX | Polk | 38 min |
| Apr 18, 6:41 AM CDT | Marine Weather Statement | HGX | 2 hr | |
| Apr 18, 7:39 AM CDT | Areal Flood Advisory | HGX | Burleson, Washington | 3 hr |
| Apr 18, 9:35 AM CDT | Small Craft Advisory | HGX | 9 hr | |
| Apr 18, 9:37 AM CDT | Tornado Warning | HGX | Grimes, Madison, Walker | 23 min |
| Apr 18, 9:47 AM CDT | Tornado Warning | HGX | Austin, Colorado, Washington | 43 min |
| Apr 18, 9:54 AM CDT | River Flood Warning | HGX | Jackson | 4 days |
| Apr 18, 10:32 AM CDT | Tornado Warning | HGX | Washington | 28 min |
| Apr 18, 10:49 AM CDT | Tornado Warning | HGX | Grimes, Walker | 26 min |
| Apr 18, 10:52 AM CDT | Areal Flood Advisory | HGX | Austin, Colorado, Washington | 3 hr |
| Apr 18, 11:12 AM CDT | Areal Flood Advisory | HGX | Grimes, Harris, Montgomery, Waller | 3 hr |
| Apr 18, 11:33 AM CDT | Areal Flood Advisory | HGX | Grimes, Harris, Montgomery, Waller | 2 hr |
| Apr 18, 11:40 AM CDT | Severe Thunderstorm Warning | HGX | Wharton | 50 min |
| Apr 18, 11:44 AM CDT | Areal Flood Advisory | HGX | Fort Bend, Wharton | 2 hr |
| Apr 18, 12:02 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Fort Bend, Wharton | 43 min |
| Apr 18, 12:08 PM CDT | Tornado Warning | HGX | Brazoria, Fort Bend, Wharton | 37 min |
| Apr 18, 12:15 PM CDT | Severe Thunderstorm Warning | HGX | Liberty, Montgomery, San Jacinto | 45 min |
| Apr 18, 12:26 PM CDT | Special Marine Warning | HGX | 64 min | |
| Apr 18, 12:43 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Fort Bend | 47 min |
| Apr 18, 12:46 PM CDT | Flash Flood Warning | HGX | Harris, Montgomery | 119 min |
| Apr 18, 1:22 PM CDT | Flash Flood Warning | HGX | Brazoria, Fort Bend, Galveston | 3 hr |
| Apr 18, 1:29 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Fort Bend, Galveston, Harris | 46 min |
| Apr 18, 1:30 PM CDT | Severe Thunderstorm Warning | HGX | Fort Bend, Wharton | 45 min |
| Apr 18, 1:42 PM CDT | Flash Flood Warning | HGX | Chambers, Harris | 3 hr |
| Apr 18, 2:02 PM CDT | Flash Flood Warning | HGX | Austin, Colorado, Fort Bend, Wharton | 3 hr |
| Apr 18, 2:06 PM CDT | Severe Thunderstorm Warning | HGX | Brazoria, Galveston, Harris | 24 min |
| Apr 18, 2:13 PM CDT | Special Marine Warning | HGX | 92 min | |
| Apr 18, 3:04 PM CDT | River Flood Warning | HGX | Austin, Fort Bend, Wharton | 55 hr |
| Apr 18, 3:05 PM CDT | Special Marine Warning | HGX | 55 min | |
| Apr 18, 3:05 PM CDT | Severe Thunderstorm Warning | HGX | Chambers, Galveston, Harris | 40 min |
| Apr 18, 3:20 PM CDT | Coastal Flood Statement | HGX | Chambers, Galveston | 3 hr |
| Apr 18, 3:33 PM CDT | Severe Thunderstorm Warning | HGX | Chambers | 42 min |
| Apr 18, 3:46 PM CDT | Tornado Warning | HGX | Brazoria, Galveston | 29 min |
| Apr 18, 4:04 PM CDT | Tornado Warning | HGX | Galveston | 19 min |
| Apr 18, 4:07 PM CDT | River Flood Warning | HGX | Galveston, Harris | 38 hr |
| Apr 18, 4:07 PM CDT | Special Marine Warning | HGX | 53 min | |
| Apr 18, 4:12 PM CDT | Severe Thunderstorm Warning | HGX | Galveston | 33 min |
| Apr 18, 4:15 PM CDT | Flash Flood Warning | HGX | Brazoria, Chambers, Galveston, Harris | 3 hr |
| Apr 18, 4:19 PM CDT | Severe Thunderstorm Warning | HGX | Chambers | 41 min |
| Apr 18, 4:23 PM CDT | Areal Flood Advisory | HGX | Harris | 3 hr |
| Apr 18, 4:24 PM CDT | River Flood Warning | HGX | Harris | 18 hr |
| Apr 18, 4:24 PM CDT | Special Marine Warning | HGX | 96 min | |
| Apr 18, 4:46 PM CDT | Areal Flood Advisory | HGX | Brazoria | 3 hr |
| Apr 18, 4:59 PM CDT | Areal Flood Advisory | HGX | Brazoria, Matagorda, Wharton | 2 hr |
| Apr 18, 4:59 PM CDT | River Flood Warning | HGX | Harris | 17 hr |
| Apr 18, 5:21 PM CDT | River Flood Warning | HGX | Montgomery | 52 hr |
| Apr 18, 5:21 PM CDT | River Flood Warning | HGX | Harris, Liberty | 17 hr |
| Apr 18, 5:21 PM CDT | River Flood Warning | HGX | Montgomery | 17 hr |
| Apr 18, 5:21 PM CDT | River Flood Warning | HGX | Harris, Montgomery | 4 hr |
| Apr 18, 5:21 PM CDT | River Flood Warning | HGX | Harris, Montgomery | 17 hr |
| Apr 18, 5:37 PM CDT | River Flood Warning | HGX | Galveston, Harris | 27 hr |
Nearby
Severe Thunderstorm Warnings in Texas, 2009Every severe thunderstorm warning in 2009
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.