Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 341

March 30, 200929 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2009, 10:27 PM CDT for 29 counties in Texas. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued: Mar 30, 2009, 10:27 PM CDT (03:27 UTC)
Expired: Mar 31, 2009, 12:00 AM CDT
In force: 93 min
Issued by: the Storm Prediction Center

All 29 counties

Camp County, TX, Collin County, TX, Cooke County, TX, Dallas County, TX, Delta County, TX, Denton County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Henderson County, TX, Hood County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Montague County, TX, Morris County, TX, Parker County, TX, Rains County, TX, Rockwall County, TX, Smith County, TX, Tarrant County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wise County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 72 km from the middle of the area, began a volume at 03:31 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, 3.5 hours before the alert went out and 62 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: 650 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 1357 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 216 m²/s²
0-3 km storm-relative helicity: 415 m²/s²
Significant tornado parameter: 0.7
Supercell composite: 12.5

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
Mar 30, 7:40 PM CDT	Mesoscale Discussion	SPC	Clay, Cooke, Grayson	2 hr
Mar 30, 8:31 PM CDT	Mesoscale Discussion	SPC	Collin, Cooke, Dallas, Delta, Denton, Fannin and 11 more	89 min
Mar 30, 8:49 PM CDT	Severe Thunderstorm Watch	SPC	Collin, Cooke, Dallas, Delta, Denton, Ellis and 16 more	5 hr
Mar 30, 11:42 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Collin, Dallas, Delta and 21 more	2 hr
Mar 31, 11:54 AM CDT	Mesoscale Discussion	SPC	Newton, Orange	96 min
Mar 31, 2:44 PM CDT	Mesoscale Discussion	SPC	Newton, Orange	91 min

Nearby

Mesoscale Discussions in Texas, 2009 Every mesoscale discussion in 2009

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.