Alert archive / Iowa / Severe Thunderstorm Watches in 2004
Severe Thunderstorm Watch 684
The Storm Prediction Center issued this severe thunderstorm watch at Aug 2, 2004, 12:20 AM CDT for 10 counties in Iowa; 4 counties in Minnesota; 5 counties in South Dakota. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 2, 2004, 12:20 AM CDT (05:20 UTC)
- Expired
- Aug 2, 2004, 4:00 AM CDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
Counties Buena Vista County, IA, Cherokee County, IA, Ida County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Plymouth County, IA, Sac County, IA, Sioux County, IA, Woodbury County, IA, Murray County, MN, Nobles County, MN, Pipestone County, MN, Rock County, MN, Lake County, SD, Lincoln County, SD, Minnehaha County, SD, Moody County, SD, Union County, SD
The radar
The Sioux Falls radar (KFSD), 69 km from the middle of the area, began a volume at 05:23 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.
Warnings issued inside it
3 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 12:56 AM CDT | Severe Thunderstorm Warning | FSD | Lake | 34 min |
| Aug 2, 1:11 AM CDT | Severe Thunderstorm Warning | FSD | McCook, Minnehaha | 49 min |
| Aug 2, 2:27 AM CDT | Severe Thunderstorm Warning | FSD | Lincoln | 33 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
Omaha, NE (KOAX), launched 00:00Z, 5.3 hours before the alert went out and 231 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
- 5168 J/kg
- Mixed-layer CIN
- -53 J/kg
- Mixed-layer LCL
- 975 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km storm-relative helicity
- 139 m²/s²
- 0-3 km storm-relative helicity
- 252 m²/s²
- Significant tornado parameter
- 8.0
- Supercell composite
- 27.6
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 3:02 AM CDT | Mesoscale Discussion | SPC | Buena Vista, Cherokee, Ida, Lyon, O'Brien, Osceola and 4 more | 58 min |
| Aug 2, 4:56 AM CDT | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Benton, Black Hawk and 50 more | 94 min |
| Aug 1, 7:22 PM CDT | Mesoscale Discussion | SPC | Big Stone, Lac qui Parle, Lincoln, Swift | 53 min |
| Aug 2, 12:53 AM CDT | Mesoscale Discussion | SPC | Becker, Beltrami, Cass, Clay, Clearwater, Hubbard and 12 more | 97 min |
| Aug 2, 3:00 AM CDT | Severe Thunderstorm Watch | SPC | Anoka, Becker, Benton, Clay, Douglas, Grant and 14 more | 5 hr |
| Aug 2, 5:17 AM CDT | Mesoscale Discussion | SPC | Anoka, Becker, Benton, Clay, Douglas, Grant and 14 more | 88 min |
| Aug 2, 6:41 AM CDT | Mesoscale Discussion | SPC | Anoka, Becker, Benton, Clay, Douglas, Grant and 14 more | 64 min |
| Aug 2, 3:12 PM CDT | Mesoscale Discussion | SPC | Blue Earth, Brown, Cottonwood, Dodge, Faribault, Freeborn and 18 more | 2 hr |
| Aug 2, 3:50 PM CDT | Severe Thunderstorm Watch | SPC | Blue Earth, Brown, Cottonwood, Faribault, Freeborn, Jackson and 14 more | 5 hr |
| Aug 1, 7:45 PM CDT | Tornado Watch | SPC | Beadle, Brookings, Brown, Buffalo, Campbell, Clark and 26 more | 6 hr |
| Aug 1, 10:00 PM CDT | Mesoscale Discussion | SPC | Beadle, Buffalo, Campbell, Edmunds, Faulk, Hand and 7 more | 60 min |
| Aug 1, 10:35 PM CDT | Severe Thunderstorm Watch | SPC | Aurora, Bon Homme, Brule, Charles Mix, Clay, Davison and 6 more | 5 hr |
| Aug 1, 11:29 PM CDT | Mesoscale Discussion | SPC | Aurora, Beadle, Bon Homme, Brule, Buffalo, Charles Mix and 19 more | 61 min |
| Aug 2, 4:23 PM CDT | Mesoscale Discussion | SPC | Bon Homme, Charles Mix, Clay, Douglas, Gregory, Hutchinson and 5 more | 37 min |
| Aug 2, 6:30 PM CDT | Severe Thunderstorm Watch | SPC | Aurora, Bennett, Bon Homme, Brule, Buffalo, Charles Mix and 17 more | 6 hr |
Nearby
Severe Thunderstorm Watches in Iowa, 2004Severe Thunderstorm Watches in South Dakota, 2004Severe Thunderstorm Watches in Minnesota, 2004Every severe thunderstorm watch in 2004
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.