Alert archive / Texas / Mesoscale Discussions in 2011
Mesoscale Discussion 670
The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2011, 4:58 PM CDT for Little River County, Sevier County, Arkansas; 4 counties in Oklahoma; 26 counties in Texas. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- Apr 30, 2011, 4:58 PM CDT (21:58 UTC)
- Expired
- Apr 30, 2011, 6:30 PM CDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
All 32 counties
Little River County, AR, Sevier County, AR, Bryan County, OK, Choctaw County, OK, McCurtain County, OK, Pushmataha County, OK, Bosque County, TX, Bowie County, TX, Camp County, TX, Collin County, TX, Coryell County, TX, Dallas County, TX, Delta County, TX, Ellis County, TX, Fannin County, TX, Franklin County, TX, Hill County, TX, Hopkins County, TX, Hunt County, TX, Johnson County, TX, Kaufman County, TX, Lamar County, TX, Lampasas County, TX, McLennan County, TX, Morris County, TX, Navarro County, TX, Rains County, TX, Red River County, TX, Rockwall County, TX, Titus County, TX, Van Zandt County, TX, Wood County, TX
The radar
The Dallas/Ft Worth radar (KFWS), 106 km from the middle of the area, began a volume at 21:58 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 12:00Z, 10.0 hours before the alert went out and 104 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.
- Mixed-layer CAPE
- 759 J/kg
- Mixed-layer CIN
- -675 J/kg
- Mixed-layer LCL
- 611 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 490 m²/s²
- 0-3 km storm-relative helicity
- 546 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 30, 5:55 PM CDT | Tornado Watch | SPC | Hempstead, Howard, Little River, Miller, Sevier | 8 hr |
| Apr 30, 6:31 PM CDT | Mesoscale Discussion | SPC | Baxter, Clay, Cleburne, Conway, Craighead, Crittenden and 29 more | 29 min |
| Apr 30, 6:48 PM CDT | Tornado Watch | SPC | Arkansas, Clark, Cleburne, Conway, Craighead, Cross and 27 more | 7 hr |
Nearby
Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Oklahoma, 2011Mesoscale Discussions in Arkansas, 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.