Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 809

May 27, 20156 counties in Oklahoma; 9 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 27, 2015, 2:13 PM CDT for 6 counties in Oklahoma; 9 counties in Texas. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: May 27, 2015, 2:13 PM CDT (19:13 UTC)
Expired: May 27, 2015, 3:45 PM CDT
In force: 92 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

Counties Beaver County, OK, Beckham County, OK, Ellis County, OK, Harmon County, OK, Harper County, OK, Roger Mills County, OK, Childress County, TX, Collingsworth County, TX, Donley County, TX, Gray County, TX, Hemphill County, TX, Lipscomb County, TX, Ochiltree County, TX, Roberts County, TX, Wheeler County, TX

The radar

The Amarillo radar (KAMA), 154 km from the middle of the area, began a volume at 19:13 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.

Tornado Watch 231May 27, 2:45 PM CDT

The nearest sounding before it

Amarillo Airport, TX (KAMA), launched 12:00Z, 7.2 hours before the alert went out and 154 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: 529 J/kg
Mixed-layer CIN: -131 J/kg
Mixed-layer LCL: 1642 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 99 m²/s²
0-3 km storm-relative helicity: 187 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.7

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
May 26, 7:55 PM CDT	Mesoscale Discussion	SPC	Alfalfa, Blaine, Caddo, Canadian, Cleveland, Comanche and 9 more	95 min
May 26, 10:56 PM CDT	Mesoscale Discussion	SPC	Blaine, Caddo, Canadian, Cherokee, Cleveland, Creek and 21 more	94 min
May 27, 2:46 PM CDT	Tornado Watch	SPC	Beaver, Beckham, Custer, Dewey, Ellis, Greer and 6 more	10 hr
May 27, 6:16 PM CDT	Mesoscale Discussion	SPC	Beaver, Beckham, Ellis, Greer, Harper, Kiowa and 3 more	119 min
May 26, 8:25 PM CDT	Mesoscale Discussion	SPC	Coke, Coleman, Concho, Irion, Kimble, McCulloch and 6 more	95 min
May 26, 8:51 PM CDT	Mesoscale Discussion	SPC	Callahan, Comanche, Eastland, Erath, Hood, Jack and 8 more	84 min
May 26, 9:27 PM CDT	Severe Thunderstorm Watch	SPC	Bosque, Brown, Callahan, Coleman, Collin, Comanche and 37 more	6 hr
May 26, 11:47 PM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Bosque, Comanche, Coryell, Erath and 16 more	88 min
May 27, 4:48 AM CDT	Mesoscale Discussion	SPC	Austin, Chambers, Fort Bend, Hardin, Harris, Jasper and 13 more	117 min
May 27, 11:39 AM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Bexar, Blanco, Caldwell, Comal and 16 more	66 min
May 27, 3:09 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Brown, Callahan, Clay, Coleman and 18 more	2 hr
May 27, 5:05 PM CDT	Mesoscale Discussion	SPC	Andrews, Bailey, Borden, Briscoe, Castro, Cochran and 23 more	115 min

Nearby

Mesoscale Discussions in Texas, 2015 Mesoscale Discussions in Oklahoma, 2015 Every 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.