Alert archive / Arkansas / Mesoscale Discussions in 2011
Mesoscale Discussion 510
The Storm Prediction Center issued this mesoscale discussion at Apr 21, 2011, 6:13 PM CDT for 4 states. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- Apr 21, 2011, 6:13 PM CDT (23:13 UTC)
- Expired
- Apr 21, 2011, 7:45 PM CDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
All 35 counties
Benton County, AR, Crawford County, AR, Franklin County, AR, Garland County, AR, Johnson County, AR, Logan County, AR, Madison County, AR, Perry County, AR, Saline County, AR, Scott County, AR, Sebastian County, AR, Washington County, AR, Yell County, AR, Bourbon County, KS, Cherokee County, KS, Crawford County, KS, Barry County, MO, Barton County, MO, Cedar County, MO, Dade County, MO, Jasper County, MO, Lawrence County, MO, McDonald County, MO, Newton County, MO, St. Clair County, MO, Vernon County, MO, Adair County, OK, Cherokee County, OK, Craig County, OK, Delaware County, OK, Mayes County, OK, Muskogee County, OK, Ottawa County, OK, Sequoyah County, OK, Wagoner County, OK
The radar
The Western Arkansas radar (KSRX), 98 km from the middle of the area, began a volume at 23:13 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
Springfield, MO (KSGF), launched 12:00Z, 11.2 hours before the alert went out and 99 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1583 m above ground
- 0-6 km bulk shear
- 60 kt
- 0-1 km storm-relative helicity
- 68 m²/s²
- 0-3 km storm-relative helicity
- 289 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 20, 7:45 PM CDT | Severe Thunderstorm Watch | SPC | Ashley, Chicot | 6 hr |
| Apr 20, 10:22 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Chicot, Desha, Drew, Lincoln | 83 min |
| Apr 21, 2:25 PM CDT | Mesoscale Discussion | SPC | Benton, Clark, Conway, Crawford, Dallas, Franklin and 19 more | 65 min |
| Apr 21, 2:35 PM CDT | Severe Thunderstorm Watch | SPC | Baxter, Benton, Boone, Carroll, Clark, Conway and 22 more | 7 hr |
Nearby
Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Missouri, 2011Mesoscale Discussions in Oklahoma, 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.