Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 291

April 13, 20156 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 13, 2015, 2:48 PM CDT for 6 counties in Texas. It was in force for 117 min.

The area

The outline as issued.

The facts

Issued: Apr 13, 2015, 2:48 PM CDT (19:48 UTC)
Expired: Apr 13, 2015, 4:45 PM CDT
In force: 117 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties Brown County, TX, Coke County, TX, Coleman County, TX, Mitchell County, TX, Nolan County, TX, Runnels County, TX

The radar

The San Angelo radar (KSJT), 62 km from the middle of the area, began a volume at 19:52 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 58Apr 13, 5:35 PM CDT

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 7.8 hours before the alert went out and 195 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: 54 J/kg
Mixed-layer CIN: -75 J/kg
Mixed-layer LCL: 1055 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -27 m²/s²
0-3 km storm-relative helicity: 36 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 12, 8:23 PM CDT	Mesoscale Discussion	SPC	Baylor, Childress, Cottle, Dickens, Foard, Hall and 5 more	97 min
Apr 12, 8:59 PM CDT	Mesoscale Discussion	SPC	Atascosa, Bandera, Brooks, Dimmit, Duval, Frio and 12 more	91 min
Apr 13, 3:55 PM CDT	Mesoscale Discussion	SPC	Brooks, Duval, Jim Hogg, Zapata	2 hr
Apr 13, 5:16 PM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Brown, Coke, Coleman, Comanche and 9 more	119 min
Apr 13, 5:33 PM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Bosque, Brown, Callahan, Coke and 22 more	4 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.