Alert archive / Arkansas / Mesoscale Discussions in 2012
Mesoscale Discussion 1783
The Storm Prediction Center issued this mesoscale discussion at Aug 18, 2012, 6:29 AM CDT for 4 states. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 18, 2012, 6:29 AM CDT (11:29 UTC)
- Expired
- Aug 18, 2012, 8:30 AM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 33 counties
Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Drew County, AR, Grant County, AR, Hempstead County, AR, Hot Spring County, AR, Howard County, AR, Lafayette County, AR, Lincoln County, AR, Little River County, AR, Miller County, AR, Nevada County, AR, Ouachita County, AR, Pike County, AR, Sevier County, AR, Union County, AR, Claiborne Parish, LA, East Carroll Parish, LA, Lincoln Parish, LA, Morehouse Parish, LA, Union Parish, LA, Webster Parish, LA, West Carroll Parish, LA, Issaquena County, MS, Sharkey County, MS, Washington County, MS, Bowie County, TX
The radar
The Little Rock radar (KLZK), 141 km from the middle of the area, began a volume at 11:29 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 (KBAD), launched 00:00Z, 11.5 hours before the alert went out and 156 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
- 1345 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 1634 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 46 m²/s²
- 0-3 km storm-relative helicity
- 65 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 |
|---|---|---|---|---|
| Aug 17, 7:53 PM CDT | Mesoscale Discussion | SPC | Ashley, Bradley, Calhoun, Chicot, Columbia, Hempstead and 7 more | 2 hr |
| Aug 18, 10:56 AM CDT | Mesoscale Discussion | SPC | East Carroll, Madison, Richland, West Carroll | 94 min |
| Aug 18, 1:10 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Clay, Cottle, Foard, Hardeman and 5 more | 2 hr |
| Aug 18, 2:05 PM CDT | Severe Thunderstorm Watch | SPC | Archer, Baylor, Briscoe, Castro, Childress, Clay and 28 more | 7 hr |
| Aug 18, 5:00 PM CDT | Mesoscale Discussion | SPC | Archer, Baylor, Briscoe, Castro, Childress, Clay and 30 more | 90 min |
Nearby
Mesoscale Discussions in Arkansas, 2012Mesoscale Discussions in Louisiana, 2012Mesoscale Discussions in Mississippi, 2012Every mesoscale discussion in 2012
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.