Alert archive / Iowa / Mesoscale Discussions in 2013
Mesoscale Discussion 1641
The Storm Prediction Center issued this mesoscale discussion at Aug 6, 2013, 5:58 PM CDT for 35 counties in Iowa. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 6, 2013, 5:58 PM CDT (22:58 UTC)
- Expired
- Aug 6, 2013, 8:00 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 35 counties
Adair County, IA, Adams County, IA, Appanoose County, IA, Benton County, IA, Boone County, IA, Cass County, IA, Clarke County, IA, Dallas County, IA, Davis County, IA, Decatur County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Iowa County, IA, Jasper County, IA, Jefferson County, IA, Keokuk County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mills County, IA, Monroe County, IA, Montgomery County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Wapello County, IA, Warren County, IA, Wayne County, IA
The radar
The Des Moines radar (KDMX), 40 km from the middle of the area, began a volume at 23:00 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
Omaha, NE (KOAX), launched 12:00Z, 11.0 hours before the alert went out and 212 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
- 2968 J/kg
- Mixed-layer CIN
- -2 J/kg
- Mixed-layer LCL
- 509 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 1 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 1.9
- Supercell composite
- 7.8
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 6, 5:07 AM CDT | Mesoscale Discussion | SPC | Fremont, Harrison, Mills, Monona, Pottawattamie, Shelby | 83 min |
| Aug 6, 6:35 AM CDT | Severe Thunderstorm Watch | SPC | Fremont, Harrison, Mills, Monona, Montgomery, Page and 2 more | 4 hr |
| Aug 6, 9:26 AM CDT | Mesoscale Discussion | SPC | Audubon, Cass, Fremont, Mills, Montgomery, Page and 2 more | 64 min |
| Aug 6, 5:22 PM CDT | Mesoscale Discussion | SPC | Buena Vista, Calhoun, Carroll, Cerro Gordo, Cherokee, Clay and 24 more | 2 hr |
| Aug 6, 6:51 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Appanoose, Audubon, Cass, Cedar and 38 more | 3 hr |
Nearby
Mesoscale Discussions in Iowa, 2013Every mesoscale discussion in 2013
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.