Alert archive / Texas / Mesoscale Discussions in 2014

Mesoscale Discussion 375

April 20, 20147 counties in Oklahoma; 10 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2014, 10:18 PM CDT for 7 counties in Oklahoma; 10 counties in Texas. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued: Apr 20, 2014, 10:18 PM CDT (03:18 UTC)
Expired: Apr 20, 2014, 11:45 PM CDT
In force: 87 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Comanche County, OK, Cotton County, OK, Jackson County, OK, Jefferson County, OK, Kiowa County, OK, Stephens County, OK, Tillman County, OK, Archer County, TX, Baylor County, TX, Clay County, TX, Haskell County, TX, Knox County, TX, Stonewall County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Altus AFB radar (KFDR), 50 km from the middle of the area, began a volume at 03:21 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, 3.3 hours before the alert went out and 277 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: 45 J/kg
Mixed-layer CIN: -57 J/kg
Mixed-layer LCL: 1981 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 38 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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.

Issued	Product	Office	Counties	Lasted
Apr 21, 2:25 PM CDT	Mesoscale Discussion	SPC	Bell, Bosque, Brown, Coleman, Collin, Comanche and 30 more	2 hr
Apr 21, 2:52 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Blanco, Bosque, Burnet, Camp and 55 more	7 hr
Apr 21, 5:09 PM CDT	Mesoscale Discussion	SPC	Bandera, Bell, Blanco, Burnet, Comal, Coryell and 15 more	96 min

Nearby

Mesoscale Discussions in Texas, 2014 Mesoscale Discussions in Oklahoma, 2014 Every mesoscale discussion in 2014

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.