Alert archive / Texas / Flash Flood Watches in 2018

Flash Flood Watch 4, NWS Houston/Galveston, TX

June 20, 20184 counties in Texas

NWS Houston/Galveston, TX issued this flash flood watch at Jun 20, 2018, 3:44 AM CDT for 4 counties in Texas. It was in force for 15 hr.

The area

The counties it named.

The facts

Issued: Jun 20, 2018, 3:44 AM CDT (08:44 UTC)
Expired: Jun 20, 2018, 7:00 PM CDT
In force: 15 hr
Issued by: NWS Houston/Galveston, TX
Flood severity: None

Counties Colorado County, TX, Jackson County, TX, Matagorda County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 126 km from the middle of the area, began a volume at 08:43 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, 8.7 hours before the alert went out and 187 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: 431 J/kg
Mixed-layer CIN: -10 J/kg
Mixed-layer LCL: 705 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: -29 m²/s²
0-3 km storm-relative helicity: -30 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 Jun 19, 11:45 PM CDT, 3 hours 59 minutes earlier.

Area forecast discussion, Jun 19, 11:45 PM CDT, 3 hours 59 minutes before

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Hazardous weather outlook, Jun 19, 7:20 PM CDT, 8 hours 24 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
Jun 20, 4:07 AM CDT	Areal Flood Advisory	HGX	Fort Bend, Harris, Waller	113 min
Jun 20, 4:54 AM CDT	Areal Flood Advisory	HGX	Jackson	3 hr
Jun 20, 5:01 AM CDT	Areal Flood Advisory	HGX	Austin, Fort Bend, Harris, Waller	3 hr
Jun 20, 5:42 AM CDT	Areal Flood Advisory	HGX	Grimes, Harris, Montgomery, Waller	2 hr
Jun 20, 5:50 AM CDT	Areal Flood Advisory	HGX	Fort Bend, Harris, Waller	115 min
Jun 20, 7:30 AM CDT	Areal Flood Advisory	HGX	Grimes, Harris, Houston, Madison, Montgomery, Walker and 1 more	3 hr
Jun 20, 9:06 AM CDT	Areal Flood Advisory	HGX	Jackson	114 min
Jun 20, 3:50 PM CDT	Small Craft Advisory	HGX		3 hr
Jun 20, 4:14 PM CDT	Areal Flood Advisory	HGX	Fort Bend, Harris, Montgomery, Waller, Wharton	2 hr
Jun 20, 5:07 PM CDT	Areal Flood Advisory	HGX	Brazoria, Fort Bend, Galveston, Harris, Montgomery	113 min
Jun 20, 5:48 PM CDT	River Flood Warning	HGX	Harris	9 hr
Jun 20, 5:53 PM CDT	River Flood Warning	HGX	Harris	8 min
Jun 20, 5:53 PM CDT	River Flood Warning	HGX	Harris	27 hr
Jun 20, 5:53 PM CDT	River Flood Warning	HGX	Jackson	45 hr

Nearby

Flash Flood Watches in Texas, 2018 Every flash flood watch in 2018

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.