Alert archive / Texas / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 258, NWS Amarillo, TX

August 17, 2009Donley County, Gray County, Texas

NWS Amarillo, TX issued this severe thunderstorm warning at Aug 17, 2009, 6:05 PM CDT for Donley County, Gray 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 17, 2009, 6:05 PM CDT (23:05 UTC)
Expired: Aug 17, 2009, 7:00 PM CDT
In force: 55 min
Issued by: NWS Amarillo, TX
Area: Storm-based polygon

Counties Donley County, TX, Gray County, TX

The radar

The Amarillo radar (KAMA), 82 km from the middle of the area, began a volume at 23:05 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 17, 3:18 PM CDT	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 11.1 hours before the alert went out and 81 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: 1647 J/kg
Mixed-layer CIN: -184 J/kg
Mixed-layer LCL: 1758 m above ground
0-6 km bulk shear: 19 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 66 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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 17, 3:40 PM CDT, 2 hours 25 minutes earlier.

Area forecast discussion, Aug 17, 3:40 PM CDT, 2 hours 25 minutes before

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Hazardous weather outlook, Aug 17, 6:03 PM CDT, 2 minutes before

TEXAS/OKLAHOMA PANHANDLES HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE AMARILLO TX
603 PM CDT MON AUG 17 2009

OKZ001>003-TXZ001>020-181100-
ARMSTRONG-BEAVER-CARSON-CIMARRON-COLLINGSWORTH-DALLAM-DEAF SMITH-
DONLEY-GRAY-HANSFORD-HARTLEY-HEMPHILL-HUTCHINSON-LIPSCOMB-MOORE-
OCHILTREE-OLDHAM-POTTER-RANDALL-ROBERTS-SHERMAN-TEXAS-WHEELER-
603 PM CDT MON AUG 17 2009

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE TEXAS AND OKLAHOMA
PANHANDLES.

.DAY ONE...

A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR THE ENTIRE TEXAS AND
OKLAHOMA PANHANDLES UNTIL 10 PM. SCATTERED TO NUMEROUS THUNDERSTORMS
ARE EXPECTED ACROSS ALL OF THE OKLAHOMA AND TEXAS PANHANDLES THROUGH
TONIGHT. A FEW OF THE STORMS THAT FORM ARE EXPECTED TO BECOME SEVERE
WITH LARGE HAIL AND DAMAGING WINDS BEING THE PRIMARY THREATS. IN
ADDITION...HEAVY RAINFALL WILL BE POSSIBLE WITH THE STRONGEST
STORMS...WHICH MAY LEAD TO LOCALIZED FLOODING OR FLASH FLOODING.

.DAYS TWO THROUGH SEVEN...

THUNDERSTORMS WILL BE POSSIBLE ACROSS MUCH OF THE TEXAS AND
OKLAHOMA PANHANDLES TUESDAY THROUGH THURSDAY. SOME OF THE STORMS THAT
DEVELOP WILL HAVE THE POTENTIAL TO BECOME SEVERE...WITH DAMAGING
WINDS AND LARGE HAIL THE PRIMARY THREATS. IN ADDITION...HEAVY
RAINFALL WILL BE POSSIBLE WITH THE STRONGEST STORMS...WHICH MAY LEAD
TO LOCALIZED FLOODING OR FLASH FLOODING.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS AND EMERGENCY MANAGEMENT GROUPS MAY BE CALLED UPON FOR
ACTIVATION THROUGH TONIGHT. SPOTTERS AND RAINFALL OBSERVERS ARE
REQUESTED TO RELAY THEIR RAINFALL REPORTS TO THE NATIONAL WEATHER
SERVICE IN AMARILLO.

TAB

In the hours before

Local storm report, Aug 17, 5:26 PM CDT, 39 minutes before

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Local storm report, Aug 17, 5:27 PM CDT, 38 minutes before

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Local storm report, Aug 17, 5:44 PM CDT, 21 minutes before

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Local storm report, Aug 17, 5:48 PM CDT, 17 minutes before

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Local storm report, Aug 17, 5:55 PM CDT, 10 minutes before

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Local storm report, Aug 17, 6:02 PM CDT, 3 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 2:57 PM CDT	Severe Thunderstorm Warning	AMA	Carson, Potter, Randall	63 min
Aug 17, 3:29 PM CDT	Severe Thunderstorm Warning	AMA	Carson, Gray	91 min
Aug 17, 4:10 PM CDT	Severe Thunderstorm Warning	AMA	Armstrong, Carson, Potter, Randall	65 min
Aug 17, 4:23 PM CDT	Severe Thunderstorm Warning	AMA	Deaf Smith, Oldham, Potter, Randall	67 min
Aug 17, 4:36 PM CDT	Areal Flood Advisory	AMA	Armstrong, Carson, Potter, Randall	3 hr
Aug 17, 4:44 PM CDT	Severe Thunderstorm Warning	AMA	Oldham, Potter	45 min
Aug 17, 4:59 PM CDT	Severe Thunderstorm Warning	AMA	Armstrong, Carson, Gray	61 min
Aug 17, 5:11 PM CDT	Severe Thunderstorm Warning	AMA	Carson, Potter	64 min
Aug 17, 5:17 PM CDT	Severe Thunderstorm Warning	AMA	Hansford, Hutchinson, Ochiltree, Roberts	58 min
Aug 17, 5:21 PM CDT	Severe Thunderstorm Warning	AMA	Hartley, Moore	54 min
Aug 17, 5:42 PM CDT	Severe Thunderstorm Warning	AMA	Hansford, Ochiltree	63 min
Aug 17, 5:45 PM CDT	Severe Thunderstorm Warning	AMA	Armstrong, Carson, Donley, Gray	60 min
Aug 17, 6:26 PM CDT	Severe Thunderstorm Warning	AMA	Hemphill, Wheeler	64 min
Aug 17, 6:39 PM CDT	Severe Thunderstorm Warning	AMA	Dallam	66 min
Aug 17, 6:43 PM CDT	Severe Thunderstorm Warning	AMA	Lipscomb, Ochiltree	62 min
Aug 17, 6:46 PM CDT	Severe Thunderstorm Warning	AMA	Armstrong, Carson, Donley, Gray	59 min

Nearby

Severe Thunderstorm Warnings in Texas, 2009 Every severe thunderstorm warning in 2009

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.