Alert archive / Texas / Mesoscale Discussions in 2009

Mesoscale Discussion 787

May 10, 20099 counties in Arkansas; 4 counties in Oklahoma; 17 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at May 10, 2009, 12:02 AM CDT for 9 counties in Arkansas; 4 counties in Oklahoma; 17 counties in Texas. It was in force for 118 min.

The area

The outline as issued.

The facts

Issued: May 10, 2009, 12:02 AM CDT (05:02 UTC)
Expired: May 10, 2009, 2:00 AM CDT
In force: 118 min
Issued by: the Storm Prediction Center

All 30 counties

Columbia County, AR, Hempstead County, AR, Howard County, AR, Lafayette County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Sevier County, AR, Bryan County, OK, Choctaw County, OK, Marshall County, OK, McCurtain County, OK, Bowie County, TX, Camp County, TX, Cass County, TX, Collin County, TX, Cooke County, TX, Delta County, TX, Denton County, TX, Fannin County, TX, Franklin County, TX, Grayson County, TX, Hopkins County, TX, Hunt County, TX, Lamar County, TX, Marion County, TX, Morris County, TX, Red River County, TX, Titus County, TX

The radar

The Shreveport radar (KSHV), 176 km from the middle of the area, began a volume at 05:03 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

Shreveport, LA (KSHV), launched 00:00Z, 5.0 hours before the alert went out and 181 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: 1854 J/kg
Mixed-layer CIN: -40 J/kg
Mixed-layer LCL: 737 m above ground
0-6 km bulk shear: 36 kt
0-1 km storm-relative helicity: 80 m²/s²
0-3 km storm-relative helicity: 164 m²/s²
Significant tornado parameter: 1.5
Supercell composite: 8.2

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.

Issued	Product	Office	Counties	Lasted
May 10, 11:17 AM CDT	Mesoscale Discussion	SPC	Ashley, Bradley, Calhoun, Chicot, Clark, Cleveland and 15 more	118 min
May 10, 3:48 PM CDT	Mesoscale Discussion	SPC	Ashley, Union	87 min

Nearby

Mesoscale Discussions in Texas, 2009 Mesoscale Discussions in Arkansas, 2009 Mesoscale Discussions in Oklahoma, 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.