Alert archive / Texas / Flash Flood Warnings in 2009

Flash Flood Warning 15, NWS Houston/Galveston, TX

April 25, 2009Brazos County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at Apr 25, 2009, 5:25 AM CDT for Brazos County, Texas. It was in force for 95 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 25, 2009, 5:25 AM CDT (10:25 UTC)
Expired: Apr 25, 2009, 7:00 AM CDT
In force: 95 min
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Flood severity: None

County Brazos County, TX

The radar

The Ft Hood radar (KGRK), 104 km from the middle of the area, began a volume at 10:28 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, 10.4 hours before the alert went out and 304 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: 1376 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 958 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 62 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Apr 25, 4:35 AM CDT, 50 minutes earlier.

Area forecast discussion, Apr 25, 4:35 AM CDT, 50 minutes before

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Hazardous weather outlook, Apr 25, 4:06 AM CDT, 1 hour 19 minutes before

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In the hours before

Local storm report, Apr 25, 1:39 AM CDT, 3 hours 46 minutes before

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Local storm report, Apr 25, 2:12 AM CDT, 3 hours 13 minutes before

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Local storm report, Apr 25, 2:45 AM CDT, 2 hours 40 minutes before

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Local storm report, Apr 25, 2:52 AM CDT, 2 hours 33 minutes before

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Local storm report, Apr 25, 2:58 AM CDT, 2 hours 27 minutes before

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Local storm report, Apr 25, 4:03 AM CDT, 1 hour 22 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 24, 7:46 PM CDT	Areal Flood Advisory	HGX	Brazoria, Fort Bend, Harris	119 min
Apr 24, 8:25 PM CDT	Areal Flood Advisory	HGX	Harris	2 hr
Apr 24, 8:41 PM CDT	Flash Flood Warning	HGX	Brazoria, Fort Bend, Galveston, Harris	3 hr
Apr 24, 8:49 PM CDT	Severe Thunderstorm Warning	HGX	Harris	26 min
Apr 24, 8:50 PM CDT	Special Marine Warning	HGX		40 min
Apr 24, 9:06 PM CDT	Severe Thunderstorm Warning	HGX	Brazoria, Galveston, Harris	24 min
Apr 24, 9:31 PM CDT	Special Marine Warning	HGX		59 min
Apr 24, 9:34 PM CDT	Severe Thunderstorm Warning	HGX	Galveston, Harris	41 min
Apr 24, 10:17 PM CDT	Small Craft Advisory	HGX		3 days
Apr 24, 10:34 PM CDT	Flash Flood Warning	HGX	Chambers	6 hr
Apr 24, 10:41 PM CDT	Severe Thunderstorm Warning	HGX	Chambers	64 min
Apr 24, 11:21 PM CDT	Special Marine Warning	HGX		54 min
Apr 24, 11:47 PM CDT	Flash Flood Warning	HGX	Brazoria, Galveston, Harris	118 min
Apr 25, 1:22 AM CDT	River Flood Warning	HGX	Galveston, Harris	6 days
Apr 25, 1:22 AM CDT	River Flood Warning	HGX	Galveston, Harris	6 days
Apr 25, 2:33 AM CDT	Severe Thunderstorm Warning	HGX	Brazos, Burleson	42 min
Apr 25, 3:33 AM CDT	Severe Thunderstorm Warning	HGX	Brazos	27 min
Apr 25, 4:15 AM CDT	Severe Thunderstorm Warning	HGX	Brazos	30 min

Nearby

Flash Flood Warnings in Texas, 2009 Every flash flood 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.