Alert archive / Texas / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 170, NWS Amarillo, TX

August 4, 2020Moore County, Sherman County, Texas

NWS Amarillo, TX issued this severe thunderstorm warning at Aug 4, 2020, 9:50 PM CDT for Moore County, Sherman County, Texas. It was in force for 55 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 4, 2020, 9:50 PM CDT (02:50 UTC)
Expired: Aug 4, 2020, 10:45 PM CDT
In force: 55 min
Issued by: NWS Amarillo, TX
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Moore County, TX, Sherman County, TX

The radar

The Amarillo radar (KAMA), 93 km from the middle of the area, began a volume at 02:52 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

Amarillo Airport, TX (KAMA), launched 00:00Z, 2.8 hours before the alert went out and 94 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: 885 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 2764 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 25 m²/s²
0-3 km storm-relative helicity: 195 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.8

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 Amarillo, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 4, 5:56 PM CDT, 3 hours 54 minutes earlier.

Area forecast discussion, Aug 4, 5:56 PM CDT, 3 hours 54 minutes before

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Hazardous weather outlook, Aug 4, 3:43 PM CDT, 6 hours 7 minutes before

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In the hours before

Special weather statement, Aug 4, 9:12 PM CDT, 38 minutes before

Special Weather Statement
National Weather Service Amarillo TX
912 PM CDT Tue Aug 4 2020

TXZ001-002-006-007-050315-
Hartley TX-Sherman TX-Dallam TX-Moore TX-
912 PM CDT Tue Aug 4 2020

...SIGNIFICANT WEATHER ADVISORY FOR SHERMAN...SOUTHEASTERN DALLAM...
NORTHERN MOORE AND NORTHEASTERN HARTLEY COUNTIES UNTIL 1015 PM CDT...

At 912 PM CDT, Doppler radar was tracking a strong thunderstorm 5
miles east of Conlen, or 6 miles southwest of Stratford, moving east
at 35 mph.

Half inch hail and wind gusts of 50 to 55 mph will be possible with
this storm.

Locations impacted include...
Dumas, Stratford, Cactus, Sunray and Conlen.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take shelter in a sturdy building if threatening weather approaches.

&&

LAT...LON 3609 10247 3644 10222 3635 10163 3605 10163
      3579 10191
TIME...MOT...LOC 0212Z 292DEG 31KT 3626 10214

Guerrero

The office that day

Everything else NWS Amarillo, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 4, 9:12 PM CDT	Special Weather Statement	AMA	Moore, Sherman	63 min
Aug 4, 10:43 PM CDT	Severe Thunderstorm Warning	AMA	Moore	62 min
Aug 4, 11:27 PM CDT	Areal Flood Advisory	AMA	Moore, Sherman	3 hr
Aug 4, 11:49 PM CDT	Areal Flood Advisory	AMA	Dallam, Sherman	4 hr
Aug 5, 12:31 AM CDT	Special Weather Statement	AMA	Sherman	29 min
Aug 5, 12:39 AM CDT	Special Weather Statement	AMA	Moore	36 min
Aug 5, 12:54 AM CDT	Areal Flood Advisory	AMA	Carson	3 hr
Aug 5, 1:13 AM CDT	Special Weather Statement	AMA	Moore	32 min
Aug 5, 2:44 AM CDT	Areal Flood Advisory	AMA	Moore, Sherman	46 min
Aug 5, 4:52 AM CDT	Areal Flood Advisory	AMA	Hansford, Moore, Sherman	3 hr

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.