Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 485

April 16, 201320 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 16, 2013, 5:48 PM CDT for 20 counties in Texas. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued: Apr 16, 2013, 5:48 PM CDT (22:48 UTC)
Expired: Apr 16, 2013, 6:45 PM CDT
In force: 57 min
Issued by: the Storm Prediction Center
Chance of a watch: 40%

Counties Brown County, TX, Callahan County, TX, Coke County, TX, Coleman County, TX, Concho County, TX, Eastland County, TX, Fisher County, TX, Haskell County, TX, Jones County, TX, Mitchell County, TX, Nolan County, TX, Runnels County, TX, Scurry County, TX, Shackelford County, TX, Stephens County, TX, Sterling County, TX, Stonewall County, TX, Taylor County, TX, Throckmorton County, TX, Tom Green County, TX

The radar

The Dyess AFB radar (KDYX), 58 km from the middle of the area, began a volume at 22:49 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 nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 10.8 hours before the alert went out and 227 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: 852 J/kg
Mixed-layer CIN: -308 J/kg
Mixed-layer LCL: 1768 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 122 m²/s²
0-3 km storm-relative helicity: 129 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Apr 15, 7:04 PM CDT	Mesoscale Discussion	SPC	Collin, Cooke, Dallas, Denton, Fannin, Grayson and 8 more	41 min

Nearby

Mesoscale Discussions in Texas, 2013 Every mesoscale discussion in 2013

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.