Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 707

May 20, 20154 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 20, 2015, 1:35 PM CDT for 4 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: May 20, 2015, 1:35 PM CDT (18:35 UTC)
Expired: May 20, 2015, 4:00 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Crane County, TX, Pecos County, TX, Terrell County, TX, Upton County, TX

The radar

The Midland/Odessa radar (KMAF), 142 km from the middle of the area, began a volume at 18:34 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.

Severe Thunderstorm Watch 192May 20, 5:25 PM CDT

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 6.6 hours before the alert went out and 142 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: 1293 J/kg
Mixed-layer CIN: -75 J/kg
Mixed-layer LCL: 774 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: 152 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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 19, 7:15 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Callahan, Clay, Cooke, Eastland and 11 more	90 min
May 19, 8:58 PM CDT	Tornado Watch	SPC	Archer, Baylor, Clay, Foard, Hardeman, Knox and 2 more	5 hr
May 19, 9:18 PM CDT	Mesoscale Discussion	SPC	Comanche, Cooke, Denton, Eastland, Erath, Hood and 9 more	87 min
May 19, 11:15 PM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Clay, Cooke, Cottle, Fannin and 8 more	90 min
May 20, 1:10 AM CDT	Mesoscale Discussion	SPC	Archer, Baylor, Clay, Cooke, Foard, Knox and 3 more	95 min
May 20, 5:07 PM CDT	Mesoscale Discussion	SPC	Brewster, Crockett, Edwards, Kerr, Kimble, Kinney and 7 more	53 min
May 20, 5:29 PM CDT	Severe Thunderstorm Watch	SPC	Brewster, Concho, Crane, Crockett, Edwards, Irion and 13 more	6 hr

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.