Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 342

March 30, 20095 counties in Arkansas; 7 counties in Oklahoma; 27 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 30, 2009, 11:42 PM CDT for 5 counties in Arkansas; 7 counties in Oklahoma; 27 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Mar 30, 2009, 11:42 PM CDT (04:42 UTC)
Expired: Mar 31, 2009, 1:45 AM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 39 counties

Howard County, AR, Little River County, AR, Miller County, AR, Polk County, AR, Sevier County, AR, Bryan County, OK, Choctaw County, OK, Haskell County, OK, Latimer County, OK, LeFlore County, OK, McCurtain County, OK, Pushmataha County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Gregg County, TX, Harrison County, TX, Henderson County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Smith County, TX, Titus County, TX, Upshur County, TX, Van Zandt County, TX, Wood County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 189 km from the middle of the area, began a volume at 04:44 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, 4.7 hours before the alert went out and 176 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	Atoka, Bryan, Canadian, Carter, Cherokee, Cleveland and 41 more	2 hr
Mar 30, 8:31 PM CDT	Mesoscale Discussion	SPC	Love	89 min
Mar 30, 10:10 PM CDT	Mesoscale Discussion	SPC	Adair, Atoka, Carter, Cherokee, Coal, Craig and 26 more	95 min
Mar 30, 8:49 PM CDT	Severe Thunderstorm Watch	SPC	Collin, Cooke, Dallas, Delta, Denton, Ellis and 16 more	5 hr
Mar 30, 10:27 PM CDT	Mesoscale Discussion	SPC	Camp, Collin, Cooke, Dallas, Delta, Denton and 23 more	93 min
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 Mesoscale Discussions in Oklahoma, 2009 Mesoscale Discussions in Arkansas, 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.