Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 2097

December 21, 201317 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Dec 21, 2013, 9:53 AM CST for 17 counties in Texas. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: Dec 21, 2013, 9:53 AM CST (15:53 UTC)
Expired: Dec 21, 2013, 11:00 AM CST
In force: 67 min
Issued by: the Storm Prediction Center
Chance of a watch: 60%

Counties Atascosa County, TX, Bastrop County, TX, Bee County, TX, Bexar County, TX, Caldwell County, TX, DeWitt County, TX, Fayette County, TX, Goliad County, TX, Gonzales County, TX, Guadalupe County, TX, Karnes County, TX, Lavaca County, TX, Live Oak County, TX, McMullen County, TX, Refugio County, TX, Victoria County, TX, Wilson County, TX

The radar

The Austin/San Antonio radar (KEWX), 74 km from the middle of the area, began a volume at 15:52 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 581Dec 21, 10:25 AM CST

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 12:00Z, 3.9 hours before the alert went out and 156 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: 867 J/kg
Mixed-layer CIN: -194 J/kg
Mixed-layer LCL: 568 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 315 m²/s²
0-3 km storm-relative helicity: 319 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.1

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
Dec 20, 6:44 PM CST	Mesoscale Discussion	SPC	Bowie, Cass, Morris	91 min
Dec 20, 8:18 PM CST	Mesoscale Discussion	SPC	Hardeman, Wichita, Wilbarger	6 hr
Dec 20, 10:42 PM CST	Mesoscale Discussion	SPC	Anderson, Bowie, Camp, Cass, Cherokee, Freestone and 14 more	2 hr
Dec 21, 2:31 AM CST	Mesoscale Discussion	SPC	Anderson, Angelina, Bowie, Brazos, Cass, Cherokee and 20 more	2 hr
Dec 21, 6:20 AM CST	Mesoscale Discussion	SPC	Bell, Blanco, Bosque, Brown, Burnet, Coleman and 31 more	115 min
Dec 21, 7:57 AM CST	Mesoscale Discussion	SPC	Angelina, Brazoria, Chambers, Fort Bend, Galveston, Hardin and 22 more	63 min
Dec 21, 9:46 AM CST	Tornado Watch	SPC	Angelina, Austin, Brazoria, Brazos, Burleson, Chambers and 33 more	8 hr
Dec 21, 10:29 AM CST	Severe Thunderstorm Watch	SPC	Aransas, Atascosa, Bastrop, Bee, Caldwell, Calhoun and 14 more	3 hr
Dec 21, 12:30 PM CST	Mesoscale Discussion	SPC	Angelina, Austin, Brazoria, Chambers, Fort Bend, Galveston and 20 more	60 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.