Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 758

May 21, 20136 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 21, 2013, 4:55 PM CDT for 6 counties in Texas. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: May 21, 2013, 4:55 PM CDT (21:55 UTC)
Expired: May 21, 2013, 6:30 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

Counties Brazos County, TX, Burleson County, TX, Houston County, TX, Madison County, TX, Trinity County, TX, Walker County, TX

The radar

The Ft Hood radar (KGRK), 123 km from the middle of the area, began a volume at 21:54 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 208May 21, 6:55 PM CDT

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 9.9 hours before the alert went out and 251 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: 1513 J/kg
Mixed-layer CIN: -271 J/kg
Mixed-layer LCL: 793 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 316 m²/s²
0-3 km storm-relative helicity: 251 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.6

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 20, 8:45 PM CDT	Mesoscale Discussion	SPC	Bosque, Brown, Burnet, Callahan, Clay, Coleman and 37 more	60 min
May 21, 8:12 AM CDT	Mesoscale Discussion	SPC	Archer, Clay, Collin, Cooke, Delta, Denton and 9 more	93 min
May 21, 10:09 AM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Bowie, Brown, Callahan, Camp and 57 more	96 min
May 21, 10:26 AM CDT	Tornado Watch	SPC	Anderson, Archer, Baylor, Bell, Bosque, Brown and 58 more	10 hr
May 21, 10:45 AM CDT	Severe Thunderstorm Watch	SPC	Foard, Hardeman, Knox, Wichita, Wilbarger	6 hr
May 21, 1:19 PM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Brown, Collin, Comanche, Concho and 38 more	116 min
May 21, 1:35 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Cass, Cherokee, Delta and 17 more	115 min
May 21, 1:50 PM CDT	Tornado Watch	SPC	Angelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more	8 hr
May 21, 3:18 PM CDT	Mesoscale Discussion	SPC	Anderson, Bosque, Bowie, Camp, Cass, Cherokee and 39 more	87 min
May 21, 5:54 PM CDT	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Cass, Cherokee, Gregg and 11 more	66 min
May 21, 6:55 PM CDT	Severe Thunderstorm Watch	SPC	Brazos, Burleson, Grimes, Hardin, Houston, Jasper and 9 more	6 hr

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.