Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 831

May 28, 201534 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 28, 2015, 6:57 PM CDT for 34 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 28, 2015, 6:57 PM CDT (23:57 UTC)
Expired: May 28, 2015, 9:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 34 counties

Bandera County, TX, Bexar County, TX, Blanco County, TX, Coke County, TX, Comal County, TX, Concho County, TX, Crockett County, TX, Dimmit County, TX, Edwards County, TX, Frio County, TX, Gillespie County, TX, Glasscock County, TX, Irion County, TX, Kendall County, TX, Kerr County, TX, Kimble County, TX, Kinney County, TX, Llano County, TX, Mason County, TX, Maverick County, TX, McCulloch County, TX, Medina County, TX, Menard County, TX, Reagan County, TX, Real County, TX, Runnels County, TX, Schleicher County, TX, Sterling County, TX, Sutton County, TX, Terrell County, TX, Tom Green County, TX, Uvalde County, TX, Val Verde County, TX, Zavala County, TX

The radar

The Laughlin AFB radar (KDFX), 108 km from the middle of the area, began a volume at 23:55 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

Midland Regional, TX (KMAF), launched 12:00Z, 12.0 hours before the alert went out and 243 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: 2845 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 630 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 81 m²/s²
0-3 km storm-relative helicity: 125 m²/s²
Significant tornado parameter: 0.6
Supercell composite: 4.0

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
May 28, 2:50 AM CDT	Mesoscale Discussion	SPC	Archer, Clay, Cooke, Foard, Grayson, Montague and 2 more	2 hr
May 28, 11:45 AM CDT	Mesoscale Discussion	SPC	Andrews, Borden, Cochran, Cottle, Crosby, Dawson and 28 more	90 min
May 28, 12:44 PM CDT	Tornado Watch	SPC	Andrews, Bailey, Baylor, Borden, Brewster, Callahan and 58 more	7 hr
May 28, 2:04 PM CDT	Mesoscale Discussion	SPC	Atascosa, Austin, Bastrop, Bee, Bell, Bexar and 30 more	56 min
May 28, 2:18 PM CDT	Severe Thunderstorm Watch	SPC	Dallam, Hansford, Hartley, Lipscomb, Ochiltree, Sherman	7 hr
May 28, 2:56 PM CDT	Mesoscale Discussion	SPC	Archer, Bosque, Brown, Callahan, Clay, Coleman and 25 more	94 min
May 28, 3:26 PM CDT	Severe Thunderstorm Watch	SPC	Archer, Bell, Bosque, Brown, Clay, Coleman and 44 more	8 hr
May 28, 3:42 PM CDT	Mesoscale Discussion	SPC	Andrews, Bailey, Baylor, Borden, Brewster, Cochran and 55 more	63 min
May 28, 5:33 PM CDT	Mesoscale Discussion	SPC	Dallam, Hansford, Lipscomb, Ochiltree, Sherman	87 min

Nearby

Mesoscale Discussions in Texas, 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.