Alert archive / Texas / Mesoscale Discussions in 2012

Mesoscale Discussion 1793

August 20, 201211 counties in New Mexico; 27 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2012, 2:40 PM MDT for 11 counties in New Mexico; 27 counties in Texas. It was in force for 35 min.

The area

The outline as issued.

The facts

Issued
Aug 20, 2012, 2:40 PM MDT (20:40 UTC)
Expired
Aug 20, 2012, 3:15 PM MDT
In force
35 min
Issued by
the Storm Prediction Center
Chance of a watch
95%
All 38 counties

Chaves County, NM, Curry County, NM, De Baca County, NM, Eddy County, NM, Guadalupe County, NM, Harding County, NM, Lea County, NM, Quay County, NM, Roosevelt County, NM, San Miguel County, NM, Union County, NM, Andrews County, TX, Armstrong County, TX, Bailey County, TX, Briscoe County, TX, Castro County, TX, Cochran County, TX, Crosby County, TX, Dallam County, TX, Dawson County, TX, Deaf Smith County, TX, Floyd County, TX, Gaines County, TX, Garza County, TX, Hale County, TX, Hartley County, TX, Hockley County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Moore County, TX, Oldham County, TX, Parmer County, TX, Potter County, TX, Randall County, TX, Swisher County, TX, Terry County, TX, Yoakum County, TX

The radar

The Cannon AFB radar (KFDX), 59 km from the middle of the area, began a volume at 20:40 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 8.7 hours before the alert went out and 191 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-pSkew-T log-p diagram, Amarillo Airport, TX at 12:00Z on 2012-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Amarillo Airport, TX at 12:00Z on 2012-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 169 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2358 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
169 m²/s²
0-3 km storm-relative helicity
419 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 20, 2:59 PM MDTSevere Thunderstorm WatchSPCChaves, Curry, De Baca, Eddy, Guadalupe, Harding and 5 more7 hr
Aug 20, 5:04 PM MDTMesoscale DiscussionSPCCurry, De Baca, Lea, Quay, Roosevelt116 min

Nearby

Mesoscale Discussions in Texas, 2012Mesoscale Discussions in New Mexico, 2012Every mesoscale discussion in 2012

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.