Alert archive / Texas / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 114, NWS Houston/Galveston, TX

August 28, 2020Grimes County, Madison County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Aug 28, 2020, 5:34 PM CDT for Grimes County, Madison County, Texas. It was in force for 26 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: Aug 28, 2020, 5:34 PM CDT (22:34 UTC)
Expired: Aug 28, 2020, 6:00 PM CDT
In force: 26 min
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Grimes County, TX, Madison County, TX

The radar

The Ft Hood radar (KGRK), 136 km from the middle of the area, began a volume at 22:37 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

Shreveport, LA (KSHV), launched 12:00Z, 10.6 hours before the alert went out and 284 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: 1576 J/kg
Mixed-layer CIN: -28 J/kg
Mixed-layer LCL: 668 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: 35 m²/s²
0-3 km storm-relative helicity: 128 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

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 Aug 28, 3:35 PM CDT, 1 hour 59 minutes earlier.

Area forecast discussion, Aug 28, 3:35 PM CDT, 1 hour 59 minutes before

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In the hours before

Special weather statement, Aug 28, 3:00 PM CDT, 2 hours 34 minutes before

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Special weather statement, Aug 28, 3:05 PM CDT, 2 hours 29 minutes before

Special Weather Statement
National Weather Service Houston/Galveston TX
305 PM CDT Fri Aug 28 2020

TXZ179-282045-
Polk TX-
305 PM CDT Fri Aug 28 2020

...SPECIAL WEATHER STATEMENT...

At 305 PM CDT, Doppler radar was tracking a strong thunderstorm near
Chester, moving east at 10 mph.

Winds in excess of 30 mph will be possible with this storm.

Locations impacted include...
Corrigan and Moscow.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 3080 9480 3096 9488 3108 9469 3102 9464
      3101 9466 3090 9463
TIME...MOT...LOC 2005Z 257DEG 9KT 3094 9468

Special weather statement, Aug 28, 4:47 PM CDT, 47 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 28, 3:59 AM CDT	Heat Advisory	HGX	Austin, Brazoria, Brazos, Burleson, Chambers, Colorado and 17 more	18 hr
Aug 28, 1:06 PM CDT	Coastal Flood Advisory	HGX	Galveston	8 hr
Aug 28, 3:00 PM CDT	Special Weather Statement	HGX	Liberty	45 min
Aug 28, 3:05 PM CDT	Special Weather Statement	HGX	Polk	40 min
Aug 28, 3:07 PM CDT	Heat Advisory	HGX	Austin, Brazoria, Brazos, Burleson, Chambers, Colorado and 17 more	30 hr
Aug 28, 3:25 PM CDT	Areal Flood Advisory	HGX	Liberty	2 hr
Aug 28, 4:47 PM CDT	Special Weather Statement	HGX	Liberty	43 min
Aug 28, 5:08 PM CDT	Severe Thunderstorm Warning	HGX	Harris, Liberty, Montgomery	37 min
Aug 28, 5:48 PM CDT	Areal Flood Advisory	HGX	Harris, Montgomery	57 min
Aug 28, 6:57 PM CDT	Special Weather Statement	HGX	Harris	33 min

Nearby

Severe Thunderstorm Warnings in Texas, 2020 Every severe thunderstorm warning in 2020

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.