Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 676

May 1, 201134 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 1, 2011, 1:14 AM CDT for 34 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 1, 2011, 1:14 AM CDT (06:14 UTC)
Expired
May 1, 2011, 3:15 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
All 34 counties

Bosque County, TX, Brown County, TX, Callahan County, TX, Coleman County, TX, Collin County, TX, Comanche County, TX, Cooke County, TX, Dallas County, TX, Denton County, TX, Eastland County, TX, Ellis County, TX, Erath County, TX, Fannin County, TX, Grayson County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Hunt County, TX, Jack County, TX, Johnson County, TX, Kaufman County, TX, Montague County, TX, Palo Pinto County, TX, Parker County, TX, Rains County, TX, Rockwall 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 Dallas/Ft Worth radar (KFWS), 75 km from the middle of the area, began a volume at 06:13 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.

The nearest sounding before it

Fort Worth, TX (KFWD), launched 00:00Z, 6.2 hours before the alert went out and 83 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 2011-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 277 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 2011-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 97 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
277 J/kg
Mixed-layer CIN
-315 J/kg
Mixed-layer LCL
1957 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
97 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2

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
Apr 30, 9:26 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Franklin, Gregg, Harrison and 8 more64 min
Apr 30, 11:39 PM CDTMesoscale DiscussionSPCBowie, Cass, Morris, Red River, Titus66 min
May 1, 1:16 AM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Franklin, Gregg, Harrison and 8 more59 min
May 1, 1:40 AM CDTSevere Thunderstorm WatchSPCArcher, Baylor, Brown, Callahan, Clay, Coleman and 31 more7 hr
May 1, 3:19 AM CDTMesoscale DiscussionSPCArcher, Baylor, Callahan, Clay, Collin, Comanche and 38 more86 min
May 1, 4:45 AM CDTTornado WatchSPCAnderson, Bowie, Camp, Cass, Cherokee, Delta and 21 more4 hr
May 1, 7:29 AM CDTMesoscale DiscussionSPCArcher, Baylor, Brown, Callahan, Clay, Coleman and 34 more91 min
May 1, 8:30 AM CDTMesoscale DiscussionSPCBosque, Bowie, Camp, Cass, Collin, Cooke and 28 more30 min
May 1, 8:45 AM CDTSevere Thunderstorm WatchSPCBowie, Camp, Cass, Collin, Dallas, Delta and 21 more6 hr
May 1, 12:12 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Collin and 28 more93 min
May 1, 12:47 PM CDTTornado WatchSPCAnderson, Bowie, Camp, Cass, Cherokee, Freestone and 11 more8 hr
May 1, 3:18 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Franklin and 21 more87 min
May 1, 5:42 PM CDTMesoscale DiscussionSPCBowie, Camp, Cass, Franklin, Gregg, Marion and 6 more3 hr
May 1, 5:43 PM CDTMesoscale DiscussionSPCAnderson, Bowie, Camp, Cass, Cherokee, Franklin and 21 more92 min

Nearby

Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011

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.