Alert archive / Arkansas / Mesoscale Discussions in 2011
Mesoscale Discussion 2028
The Storm Prediction Center issued this mesoscale discussion at Aug 20, 2011, 3:56 PM CDT for 35 counties in Arkansas; 21 counties in Missouri. It was in force for 64 min.
The area
The outline as issued.
The facts
- Issued
- Aug 20, 2011, 3:56 PM CDT (20:56 UTC)
- Expired
- Aug 20, 2011, 5:00 PM CDT
- In force
- 64 min
- Issued by
- the Storm Prediction Center
All 56 counties
Benton County, AR, Boone County, AR, Calhoun County, AR, Carroll County, AR, Clark County, AR, Columbia County, AR, Conway County, AR, Crawford County, AR, Dallas County, AR, Franklin County, AR, Garland County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Johnson County, AR, Lafayette County, AR, Logan County, AR, Madison County, AR, Marion County, AR, Miller County, AR, Montgomery County, AR, Nevada County, AR, Newton County, AR, Ouachita County, AR, Perry County, AR, Pike County, AR, Pope County, AR, Saline County, AR, Scott County, AR, Searcy County, AR, Sebastian County, AR, Union County, AR, Van Buren County, AR, Washington County, AR, Yell County, AR, Barry County, MO, Barton County, MO, Camden County, MO, Cedar County, MO, Christian County, MO, Dade County, MO, Dallas County, MO, Douglas County, MO, Greene County, MO, Hickory County, MO, Jasper County, MO, Laclede County, MO, Lawrence County, MO, McDonald County, MO, Newton County, MO, Polk County, MO, St. Clair County, MO, Stone County, MO, Taney County, MO, Vernon County, MO, Webster County, MO
The radar
The Western Arkansas radar (KSRX), 92 km from the middle of the area, began a volume at 20:55 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
Springfield, MO (KSGF), launched 12:00Z, 8.9 hours before the alert went out and 171 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
- 3504 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 518 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 90 m²/s²
- 0-3 km storm-relative helicity
- 142 m²/s²
- Significant tornado parameter
- 2.2
- Supercell composite
- 14.7
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 |
|---|---|---|---|---|
| Aug 20, 6:04 PM CDT | Severe Thunderstorm Watch | SPC | Baxter, Boone, Cleburne, Fulton, Independence, Izard and 7 more | 5 hr |
| Aug 19, 11:51 PM CDT | Mesoscale Discussion | SPC | Buchanan, Cass, Clay, Jackson, Platte | 54 min |
| Aug 20, 2:28 AM CDT | Mesoscale Discussion | SPC | Bates, Benton, Camden, Cass, Clay, Dallas and 10 more | 62 min |
Nearby
Mesoscale Discussions in Arkansas, 2011Mesoscale Discussions in Missouri, 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.