Alert archive / Texas / Flash Flood Watches in 2017

Flash Flood Watch 8, NWS Houston/Galveston, TX

August 24, 201723 counties in Texas

NWS Houston/Galveston, TX issued this flash flood watch at Aug 24, 2017, 5:24 AM CDT for 23 counties in Texas. It took effect at Aug 25, 2017, 4:00 AM CDT. It was in force for 4 days.

The area

The counties it named.

The facts

Issued: Aug 24, 2017, 5:24 AM CDT (10:24 UTC)
In effect from: Aug 25, 2017, 4:00 AM CDT
Expired: Aug 29, 2017, 3:04 AM CDT
In force: 4 days
Issued by: NWS Houston/Galveston, TX
Flood severity: None

All 23 counties

Austin County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Chambers County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Jackson County, TX, Liberty County, TX, Madison County, TX, Matagorda County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 91 km from the middle of the area, began a volume at 10:26 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, 10.4 hours before the alert went out and 306 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: 13 J/kg
Mixed-layer CIN: -199 J/kg
Mixed-layer LCL: 1991 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 5 m²/s²
0-3 km storm-relative helicity: 46 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 watch 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 watch went out at Aug 24, 5:08 AM CDT, 16 minutes earlier.

Area forecast discussion, Aug 24, 5:08 AM CDT, 16 minutes before

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Hazardous weather outlook, Aug 24, 1:06 AM CDT, 4 hours 18 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
Aug 23, 7:23 PM CDT	Special Weather Statement	HGX	Brazos	52 min
Aug 23, 7:29 PM CDT	Special Weather Statement	HGX	Waller	46 min
Aug 23, 8:00 PM CDT	Areal Flood Advisory	HGX	Brazos, Burleson, Grimes, Madison	2 hr
Aug 23, 8:22 PM CDT	Special Weather Statement	HGX	Brazos, Grimes, Washington	53 min
Aug 23, 9:00 PM CDT	Flash Flood Warning	HGX	Brazos, Grimes	3 hr
Aug 23, 9:37 PM CDT	Special Weather Statement	HGX	Houston	38 min
Aug 23, 9:55 PM CDT	Areal Flood Advisory	HGX	Houston	2 hr
Aug 24, 4:23 AM CDT	Hurricane Warning	HGX	Jackson, Matagorda	48 hr
Aug 24, 4:23 AM CDT	Storm Surge Warning	HGX	Brazoria, Galveston, Jackson, Matagorda	3 days
Aug 24, 4:23 AM CDT	Tropical Storm Warning	HGX	Austin, Brazoria, Chambers, Colorado, Fort Bend, Galveston and 6 more	6 days
Aug 24, 6:36 PM CDT	Special Marine Warning	HGX		24 min

Nearby

Flash Flood Watches in Texas, 2017 Every flash flood watch in 2017

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.