Alert archive / Texas / Mesoscale Discussions in 2016

Mesoscale Discussion 425

April 20, 201633 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 20, 2016, 4:54 PM CDT for 33 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Apr 20, 2016, 4:54 PM CDT (21:54 UTC)
Expired
Apr 20, 2016, 7:00 PM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 33 counties

Armstrong County, TX, Borden County, TX, Briscoe County, TX, Carson County, TX, Childress County, TX, Collingsworth County, TX, Cottle County, TX, Crosby County, TX, Dickens County, TX, Donley County, TX, Floyd County, TX, Foard County, TX, Garza County, TX, Gray County, TX, Hale County, TX, Hall County, TX, Hansford County, TX, Hemphill County, TX, Hutchinson County, TX, Kent County, TX, King County, TX, Lubbock County, TX, Lynn County, TX, Moore County, TX, Motley County, TX, Ochiltree County, TX, Potter County, TX, Roberts County, TX, Scurry County, TX, Sherman County, TX, Stonewall County, TX, Swisher County, TX, Wheeler County, TX

The radar

The Amarillo radar (KAMA), 83 km from the middle of the area, began a volume at 21:56 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, 9.9 hours before the alert went out and 83 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 2016-04-20Temperature 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 2016-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 68 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1313 m above ground
0-6 km bulk shear
65 kt
0-1 km storm-relative helicity
68 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 8:45 PM CDTMesoscale DiscussionSPCArcher, Baylor, Bell, Blanco, Borden, Bosque and 67 more3 hr
Apr 19, 9:59 PM CDTSevere Thunderstorm WatchSPCBrown, Callahan, Coleman, Comanche, Cooke, Eastland and 16 more5 hr
Apr 19, 11:39 PM CDTMesoscale DiscussionSPCBrown, Callahan, Coke, Coleman, Collin, Comanche and 25 more2 hr
Apr 20, 1:37 AM CDTMesoscale DiscussionSPCBrown, Callahan, Coleman, Collin, Comanche, Dallas and 14 more53 min
Apr 20, 2:41 PM CDTMesoscale DiscussionSPCConcho, Crockett, Irion, Kimble, McCulloch, Mason and 6 more2 hr

Nearby

Mesoscale Discussions in Texas, 2016Every mesoscale discussion in 2016

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.