Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 419

April 22, 20154 counties in Oklahoma; 31 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 22, 2015, 2:07 PM CDT for 4 counties in Oklahoma; 31 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 22, 2015, 2:07 PM CDT (19:07 UTC)
Expired
Apr 22, 2015, 4:30 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
95%
All 35 counties

Cotton County, OK, Harmon County, OK, Jackson County, OK, Tillman County, OK, Archer County, TX, Armstrong County, TX, Baylor County, TX, Briscoe County, TX, Castro County, TX, Childress County, TX, Clay County, TX, Collingsworth County, TX, Cottle County, TX, Crosby County, TX, Deaf Smith County, TX, Dickens County, TX, Donley County, TX, Floyd County, TX, Foard County, TX, Hale County, TX, Hall County, TX, Hardeman County, TX, Haskell County, TX, King County, TX, Knox County, TX, Motley County, TX, Oldham County, TX, Parmer County, TX, Randall County, TX, Stonewall County, TX, Swisher County, TX, Throckmorton County, TX, Wichita County, TX, Wilbarger County, TX, Young County, TX

The radar

The Lubbock radar (KLBB), 121 km from the middle of the area, began a volume at 19:10 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, 7.1 hours before the alert went out and 151 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 2015-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 10 joules per kilogram.LCLLFCEL10008507005003002001001 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 2015-04-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -146 square meters per square second.1939587897Sfc1 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
10 J/kg
Mixed-layer CIN
-339 J/kg
Mixed-layer LCL
2161 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
-146 m²/s²
0-3 km storm-relative helicity
-127 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.

IssuedProductOfficeCountiesLasted
Apr 22, 2:55 AM CDTMesoscale DiscussionSPCAlfalfa, Beckham, Blaine, Caddo, Canadian, Comanche and 17 more3 hr
Apr 22, 6:24 AM CDTMesoscale DiscussionSPCCaddo, Canadian, Carter, Cleveland, Coal, Comanche and 19 more2 hr
Apr 22, 2:56 PM CDTTornado WatchSPCHarmon, Jackson, Tillman9 hr
Apr 22, 10:43 AM CDTMesoscale DiscussionSPCAransas, Atascosa, Austin, Bandera, Bastrop, Bee and 36 more2 hr
Apr 22, 11:13 AM CDTTornado WatchSPCAransas, Bee, Calhoun, Duval, Goliad, Jim Wells and 7 more7 hr
Apr 22, 12:07 PM CDTMesoscale DiscussionSPCJim Wells, Nueces83 min
Apr 22, 1:43 PM CDTMesoscale DiscussionSPCAtascosa, Austin, Bandera, Bastrop, Bexar, Caldwell and 15 more92 min
Apr 22, 2:29 PM CDTMesoscale DiscussionSPCAransas, Bee, Calhoun, Duval, Goliad, Jim Wells and 5 more61 min
Apr 22, 5:48 PM CDTMesoscale DiscussionSPCBosque, Comanche, Coryell, Ellis, Erath, Hamilton and 8 more117 min
Apr 22, 6:45 PM CDTMesoscale DiscussionSPCArcher, Armstrong, Baylor, Briscoe, Carson, Castro and 29 more2 hr

Nearby

Mesoscale Discussions in Texas, 2015Mesoscale Discussions in Oklahoma, 2015Every mesoscale discussion in 2015

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.