Alert archive / Texas / Mesoscale Discussions in 2013

Mesoscale Discussion 738

May 20, 201343 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 20, 2013, 8:45 PM CDT for 43 counties in Texas. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued
May 20, 2013, 8:45 PM CDT (01:45 UTC)
Expired
May 20, 2013, 9:45 PM CDT
In force
60 min
Issued by
the Storm Prediction Center
All 43 counties

Bosque County, TX, Brown County, TX, Burnet County, TX, Callahan County, TX, Clay County, TX, Coleman County, TX, Collin County, TX, Comanche County, TX, Concho County, TX, Cooke County, TX, Coryell County, TX, Dallas County, TX, Denton County, TX, Eastland County, TX, Erath County, TX, Fannin County, TX, Gillespie County, TX, Grayson County, TX, Hamilton County, TX, Hood County, TX, Jack County, TX, Johnson County, TX, Kerr County, TX, Kimble County, TX, Lampasas County, TX, Llano County, TX, Mason County, TX, McCulloch County, TX, Menard County, TX, Mills County, TX, Montague County, TX, Palo Pinto County, TX, Parker County, TX, Runnels County, TX, San Saba County, TX, Shackelford County, TX, Somervell County, TX, Stephens County, TX, Tarrant County, TX, Taylor County, TX, Throckmorton County, TX, Wise County, TX, Young County, TX

The radar

The Dyess AFB radar (KDYX), 63 km from the middle of the area, began a volume at 01:46 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

Fort Worth, TX (KFWD), launched 00:00Z, 1.8 hours before the alert went out and 165 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-pSkew-T log-p diagram, Fort Worth, TX at 00:00Z on 2013-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1025 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 00:00Z on 2013-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 457 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1025 J/kg
Mixed-layer CIN
-144 J/kg
Mixed-layer LCL
1909 m above ground
0-6 km bulk shear
68 kt
0-1 km storm-relative helicity
457 m²/s²
0-3 km storm-relative helicity
387 m²/s²
Significant tornado parameter
0.1
Supercell composite
4.2

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.

IssuedProductOfficeCountiesLasted
May 21, 8:12 AM CDTMesoscale DiscussionSPCArcher, Clay, Collin, Cooke, Delta, Denton and 9 more93 min
May 21, 10:09 AM CDTMesoscale DiscussionSPCAnderson, Bosque, Bowie, Brown, Callahan, Camp and 57 more96 min
May 21, 10:26 AM CDTTornado WatchSPCAnderson, Archer, Baylor, Bell, Bosque, Brown and 58 more10 hr
May 21, 10:45 AM CDTSevere Thunderstorm WatchSPCFoard, Hardeman, Knox, Wichita, Wilbarger6 hr
May 21, 1:19 PM CDTMesoscale DiscussionSPCAnderson, Bosque, Brown, Collin, Comanche, Concho and 38 more116 min
May 21, 1:35 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Delta and 17 more115 min
May 21, 1:50 PM CDTTornado WatchSPCAngelina, Bowie, Camp, Cass, Cherokee, Franklin and 15 more8 hr
May 21, 3:18 PM CDTMesoscale DiscussionSPCAnderson, Bosque, Bowie, Camp, Cass, Cherokee and 39 more87 min
May 21, 4:55 PM CDTMesoscale DiscussionSPCBrazos, Burleson, Houston, Madison, Trinity, Walker95 min
May 21, 5:54 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Gregg and 11 more66 min
May 21, 6:55 PM CDTSevere Thunderstorm WatchSPCBrazos, Burleson, Grimes, Hardin, Houston, Jasper and 9 more6 hr

Nearby

Mesoscale Discussions in Texas, 2013Every 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.