Alert archive / Texas / Areal Flood Warnings in 2021

Areal Flood Warning 19, NWS Houston/Galveston, TX

May 25, 20214 counties in Texas

NWS Houston/Galveston, TX issued this areal flood warning at May 25, 2021, 6:02 AM CDT for 4 counties in Texas. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 25, 2021, 6:02 AM CDT (11:02 UTC)
Expired: May 25, 2021, 12:00 PM CDT
In force: 6 hr
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Flood severity: None

Counties Austin County, TX, Colorado County, TX, Waller County, TX, Washington County, TX

The radar

The Houston radar (KHGX), 129 km from the middle of the area, began a volume at 11:03 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, 11.0 hours before the alert went out and 299 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: 890 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 717 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 46 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this areal 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 areal flood warning went out at May 25, 3:49 AM CDT, 2 hours 13 minutes earlier.

Area forecast discussion, May 25, 3:49 AM CDT, 2 hours 13 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
May 24, 8:15 PM CDT	River Flood Warning	HGX	Hardin, Liberty, Polk	38 hr
May 24, 8:41 PM CDT	Areal Flood Advisory	HGX	Austin, Grimes, Waller, Washington	2 hr
May 24, 9:38 PM CDT	Areal Flood Warning	HGX	Austin, Colorado, Washington	112 min
May 24, 9:39 PM CDT	Flash Flood Watch	HGX	Austin, Brazoria, Brazos, Burleson, Colorado, Fort Bend and 14 more	21 hr
May 25, 12:19 AM CDT	Areal Flood Warning	HGX	Austin, Colorado, Waller, Washington	6 hr
May 25, 9:12 AM CDT	River Flood Warning	HGX	Harris	10 hr
May 25, 12:03 PM CDT	Areal Flood Warning	HGX	Colorado	6 hr
May 25, 1:17 PM CDT	Special Weather Statement	HGX	Grimes	58 min
May 25, 2:31 PM CDT	Areal Flood Advisory	HGX	Austin, Colorado, Waller	3 hr
May 25, 3:48 PM CDT	Areal Flood Advisory	HGX	Grimes, Harris, Montgomery, Waller	3 hr
May 25, 5:19 PM CDT	Special Weather Statement	HGX	Polk	41 min

Nearby

Areal Flood Warnings in Texas, 2021 Every areal flood warning in 2021

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.