Alert archive / Texas / Mesoscale Discussions in 2014

Mesoscale Discussion 415

April 27, 201421 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2014, 9:03 AM CDT for 21 counties in Texas. It was in force for 27 min.

The area

The outline as issued.

The facts

Issued: Apr 27, 2014, 9:03 AM CDT (14:03 UTC)
Expired: Apr 27, 2014, 9:30 AM CDT
In force: 27 min
Issued by: the Storm Prediction Center
Chance of a watch: 95%

All 21 counties

Anderson County, TX, Collin County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Falls County, TX, Fannin County, TX, Freestone County, TX, Henderson County, TX, Hill County, TX, Hunt County, TX, Kaufman County, TX, Lamar County, TX, Leon County, TX, Limestone County, TX, McLennan County, TX, Navarro County, TX, Rains County, TX, Robertson County, TX, Rockwall County, TX, Van Zandt County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 107 km from the middle of the area, began a volume at 14:06 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 94Apr 27, 9:15 AM CDT

The nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 2.1 hours before the alert went out and 116 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: 2370 J/kg
Mixed-layer CIN: -265 J/kg
Mixed-layer LCL: 662 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 453 m²/s²
0-3 km storm-relative helicity: 548 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

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 27, 5:09 AM CDT	Mesoscale Discussion	SPC	Clay, Wichita	96 min
Apr 27, 7:55 AM CDT	Mesoscale Discussion	SPC	Clay, Collin, Cooke, Dallas, Delta, Denton and 10 more	95 min
Apr 27, 9:16 AM CDT	Severe Thunderstorm Watch	SPC	Anderson, Bell, Collin, Delta, Falls, Fannin and 16 more	6 hr
Apr 27, 11:27 AM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Bosque, Camp, Collin, Coryell and 27 more	93 min
Apr 27, 12:25 PM CDT	Mesoscale Discussion	SPC	Bowie, Cass, Marion, Morris, Red River	2 hr
Apr 27, 1:46 PM CDT	Tornado Watch	SPC	Bowie, Camp, Cass, Franklin, Gregg, Harrison and 7 more	9 hr
Apr 27, 2:56 PM CDT	Severe Thunderstorm Watch	SPC	Delta, Ellis, Fannin, Henderson, Hopkins, Hunt and 6 more	5 hr
Apr 27, 4:52 PM CDT	Mesoscale Discussion	SPC	Bowie, Cass, Marion, Morris, Red River, Titus	53 min
Apr 27, 5:14 PM CDT	Mesoscale Discussion	SPC	Delta, Falls, Freestone, Henderson, Hopkins, Hunt and 6 more	91 min
Apr 27, 6:11 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Franklin, Harrison, Marion and 4 more	64 min
Apr 27, 6:28 PM CDT	Mesoscale Discussion	SPC	Bastrop, Brazos, Burleson, Caldwell, Fayette, Lee and 3 more	92 min

Nearby

Mesoscale Discussions in Texas, 2014 Every mesoscale discussion in 2014

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.