Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 508

May 4, 201520 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 4, 2015, 7:55 PM CDT for 20 counties in Texas. It was in force for 65 min.

The area

The outline as issued.

The facts

Issued: May 4, 2015, 7:55 PM CDT (00:55 UTC)
Expired: May 4, 2015, 9:00 PM CDT
In force: 65 min
Issued by: the Storm Prediction Center

Counties Andrews County, TX, Brewster County, TX, Crane County, TX, Crockett County, TX, Ector County, TX, Glasscock County, TX, Howard County, TX, Irion County, TX, Loving County, TX, Martin County, TX, Midland County, TX, Pecos County, TX, Reagan County, TX, Reeves County, TX, Sterling County, TX, Terrell County, TX, Upton County, TX, Val Verde County, TX, Ward County, TX, Winkler County, TX

The radar

The Midland/Odessa radar (KMAF), 184 km from the middle of the area, began a volume at 00:58 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 131May 4, 7:55 PM CDT

The nearest sounding before it

Midland Regional, TX (KMAF), launched 00:00Z, 0.9 hours before the alert went out and 184 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: 544 J/kg
Mixed-layer CIN: -36 J/kg
Mixed-layer LCL: 1484 m above ground
0-6 km bulk shear: 33 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 146 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.7

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 4, 7:12 PM CDT	Mesoscale Discussion	SPC	Andrews, Brewster, Crane, Crockett, Ector, Loving and 10 more	93 min
May 4, 7:53 PM CDT	Tornado Watch	SPC	Andrews, Brewster, Crane, Crockett, Ector, Glasscock and 12 more	6 hr
May 4, 10:05 PM CDT	Mesoscale Discussion	SPC	Andrews, Crane, Crockett, Ector, Loving, Martin and 9 more	115 min
May 5, 1:51 PM CDT	Mesoscale Discussion	SPC	Coke, Concho, Crockett, Fisher, Glasscock, Irion and 12 more	114 min
May 5, 2:01 PM CDT	Mesoscale Discussion	SPC	Parmer	89 min
May 5, 2:58 PM CDT	Mesoscale Discussion	SPC	Andrews, Bailey, Borden, Cochran, Crosby, Dawson and 12 more	92 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.