Alert archive / Iowa / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 770
The Storm Prediction Center issued this severe thunderstorm watch at Jul 20, 2003, 6:45 AM CDT for 28 counties in Iowa; 21 counties in Minnesota; Brookings County, South Dakota. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 20, 2003, 6:45 AM CDT (11:45 UTC)
- Expired
- Jul 20, 2003, 12:00 PM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 50 counties
Buena Vista County, IA, Butler County, IA, Calhoun County, IA, Cerro Gordo County, IA, Cherokee County, IA, Clay County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Humboldt County, IA, Ida County, IA, Kossuth County, IA, Lyon County, IA, O'Brien County, IA, Osceola County, IA, Palo Alto County, IA, Pocahontas County, IA, Sac County, IA, Sioux County, IA, Webster County, IA, Winnebago County, IA, Worth County, IA, Wright County, IA, Blue Earth County, MN, Brown County, MN, Cottonwood County, MN, Faribault County, MN, Freeborn County, MN, Jackson County, MN, Le Sueur County, MN, Lincoln County, MN, Lyon County, MN, Martin County, MN, Murray County, MN, Nicollet County, MN, Nobles County, MN, Pipestone County, MN, Redwood County, MN, Rice County, MN, Rock County, MN, Sibley County, MN, Steele County, MN, Waseca County, MN, Watonwan County, MN, Brookings County, SD
The radar
The Minneapolis radar (KMPX), 148 km from the middle of the area, began a volume at 11:47 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
11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 9:12 AM CDT | Severe Thunderstorm Warning | FSD | Lyon | 33 min |
| Jul 20, 9:22 AM CDT | Severe Thunderstorm Warning | FSD | O'Brien | 38 min |
| Jul 20, 9:41 AM CDT | Severe Thunderstorm Warning | FSD | O'Brien, Sioux | 34 min |
| Jul 20, 10:08 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee, O'Brien, Plymouth, Sioux | 22 min |
| Jul 20, 10:09 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee, Plymouth | 36 min |
| Jul 20, 10:11 AM CDT | Severe Thunderstorm Warning | FSD | Cottonwood | 34 min |
| Jul 20, 10:29 AM CDT | Severe Thunderstorm Warning | FSD | Buena Vista, Cherokee | 31 min |
| Jul 20, 11:00 AM CDT | Severe Thunderstorm Warning | FSD | Buena Vista | 30 min |
| Jul 20, 11:11 AM CDT | Severe Thunderstorm Warning | FSD | Rock | 34 min |
| Jul 20, 11:35 AM CDT | Severe Thunderstorm Warning | FSD | Nobles | 25 min |
| Jul 20, 11:57 AM CDT | Severe Thunderstorm Warning | FSD | Lyon, Osceola | 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
Minneapolis, MN (KMPX), launched 00:00Z, 11.8 hours before the alert went out and 147 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
- 3136 J/kg
- Mixed-layer CIN
- -1 J/kg
- Mixed-layer LCL
- 793 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 125 m²/s²
- 0-3 km storm-relative helicity
- 180 m²/s²
- Significant tornado parameter
- 2.9
- Supercell composite
- 13.4
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 20, 4:14 AM CDT | Mesoscale Discussion | SPC | Howard, Mitchell, Winnebago, Winneshiek, Worth | 3 hr |
| Jul 20, 10:07 AM CDT | Mesoscale Discussion | SPC | Buena Vista, Calhoun, Cherokee, Clay, Dickinson, Emmet and 13 more | 53 min |
| Jul 20, 2:09 PM CDT | Mesoscale Discussion | SPC | Crawford, Harrison, Monona, Plymouth, Pottawattamie, Shelby and 2 more | 66 min |
| Jul 20, 2:50 PM CDT | Tornado Watch | SPC | Adair, Adams, Audubon, Buena Vista, Carroll, Cass and 20 more | 6 hr |
| Jul 20, 5:29 PM CDT | Mesoscale Discussion | SPC | Adair, Adams, Audubon, Carroll, Cass, Cherokee and 17 more | 91 min |
| Jul 19, 7:16 PM CDT | Mesoscale Discussion | SPC | Beltrami, Clearwater, Itasca, Kittson, Koochiching, Marshall and 5 more | 89 min |
| Jul 19, 11:00 PM CDT | Severe Thunderstorm Watch | SPC | Becker, Beltrami, Clay, Clearwater, Hubbard, Mahnomen and 7 more | 5 hr |
| Jul 20, 1:15 AM CDT | Severe Thunderstorm Watch | SPC | Big Stone, Chippewa, Cottonwood, Douglas, Grant, Jackson and 15 more | 6 hr |
| Jul 20, 2:03 AM CDT | Mesoscale Discussion | SPC | Big Stone, Chippewa, Grant, Lac qui Parle, Lincoln, Lyon and 6 more | 117 min |
| Jul 20, 3:05 AM CDT | Severe Thunderstorm Watch | SPC | Becker, Clay, Grant, Norman, Otter Tail, Wilkin | 4 hr |
| Jul 20, 1:16 PM CDT | Mesoscale Discussion | SPC | Beltrami, Cook, Itasca, Koochiching, Lake, Lake of the Woods and 2 more | 119 min |
| Jul 20, 1:55 PM CDT | Severe Thunderstorm Watch | SPC | Carlton, Lake, Saint Louis | 7 hr |
| Jul 20, 3:27 PM CDT | Mesoscale Discussion | SPC | Carlton, Lake, Saint Louis | 63 min |
| Jul 20, 5:14 PM CDT | Mesoscale Discussion | SPC | Lincoln, Lyon, Murray, Pipestone, Rock, Yellow Medicine | 2 hr |
| Jul 20, 6:47 PM CDT | Mesoscale Discussion | SPC | Lake, Saint Louis | 88 min |
| Jul 19, 11:58 PM CDT | Mesoscale Discussion | SPC | Brown, Clark, Codington, Day, Deuel, Edmunds and 6 more | 62 min |
Nearby
Severe Thunderstorm Watches in Iowa, 2003Severe Thunderstorm Watches in Minnesota, 2003Severe Thunderstorm Watches in South Dakota, 2003Every severe thunderstorm watch in 2003
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.