Alert archive / Iowa / Severe Thunderstorm Watches in 2014
Severe Thunderstorm Watch 466
The Storm Prediction Center issued this severe thunderstorm watch at Aug 18, 2014, 7:44 PM CDT for 29 counties in Iowa; 13 counties in Minnesota; 15 counties in Wisconsin. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 18, 2014, 7:44 PM CDT (00:44 UTC)
- Expired
- Aug 19, 2014, 2:00 AM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 57 counties
Allamakee County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Clayton County, IA, Delaware County, IA, Dubuque County, IA, Emmet County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Howard County, IA, Humboldt County, IA, Kossuth County, IA, Mitchell County, IA, Palo Alto County, IA, Pocahontas County, IA, Webster County, IA, Winnebago County, IA, Winneshiek County, IA, Worth County, IA, Wright County, IA, Dodge County, MN, Faribault County, MN, Fillmore County, MN, Freeborn County, MN, Goodhue County, MN, Houston County, MN, Martin County, MN, Mower County, MN, Olmsted County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Winona County, MN, Adams County, WI, Buffalo County, WI, Crawford County, WI, Grant County, WI, Iowa County, WI, Jackson County, WI, Juneau County, WI, La Crosse County, WI, Lafayette County, WI, Monroe County, WI, Pepin County, WI, Richland County, WI, Sauk County, WI, Trempealeau County, WI, Vernon County, WI
The radar
The La Crosse radar (KARX), 114 km from the middle of the area, began a volume at 00:45 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 10%
- Six or more combined severe hail and wind reports
- 60%
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 7:46 PM CDT | Severe Thunderstorm Warning | MPX | Faribault, Freeborn | 29 min |
| Aug 18, 7:57 PM CDT | Severe Thunderstorm Warning | DMX | Palo Alto, Pocahontas | 48 min |
| Aug 18, 8:20 PM CDT | Severe Thunderstorm Warning | ARX | Olmsted, Wabasha | 40 min |
| Aug 18, 8:24 PM CDT | Severe Thunderstorm Warning | ARX | Mower | 51 min |
| Aug 18, 9:05 PM CDT | Severe Thunderstorm Warning | ARX | Fillmore, Houston, Olmsted, Winona | 40 min |
| Aug 18, 9:07 PM CDT | Severe Thunderstorm Warning | MPX | Freeborn | 38 min |
| Aug 18, 9:11 PM CDT | Severe Thunderstorm Warning | ARX | Howard | 31 min |
| Aug 18, 9:30 PM CDT | Severe Thunderstorm Warning | ARX | Adams, Juneau | 45 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Minneapolis, MN (KMPX), launched 00:00Z, 0.7 hours before the alert went out and 161 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
- 238 J/kg
- Mixed-layer CIN
- -45 J/kg
- Mixed-layer LCL
- 1787 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 100 m²/s²
- 0-3 km storm-relative helicity
- 105 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.2
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 9:49 PM CDT | Mesoscale Discussion | SPC | Allamakee, Black Hawk, Bremer, Buchanan, Butler, Cerro Gordo and 10 more | 56 min |
Nearby
Severe Thunderstorm Watches in Iowa, 2014Severe Thunderstorm Watches in Wisconsin, 2014Severe Thunderstorm Watches in Minnesota, 2014Every severe thunderstorm watch in 2014
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.