Alert archive / Iowa / Tornado Watches in 1998
Tornado Watch 469
The Storm Prediction Center issued this tornado watch at May 30, 1998, 8:30 PM CDT for 4 states. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 30, 1998, 8:30 PM CDT (01:30 UTC)
- Expired
- May 31, 1998, 3:00 AM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
All 70 counties
Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cherokee County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Dickinson County, IA, Emmet County, IA, Franklin County, IA, Greene County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Hardin County, IA, Harrison County, IA, Humboldt County, IA, Ida County, IA, Jasper County, IA, Kossuth County, IA, Lyon County, IA, Marshall County, IA, Monona County, IA, O'Brien County, IA, Osceola County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Polk County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Story County, IA, Webster County, IA, Winnebago County, IA, Woodbury County, IA, Wright County, IA, Faribault County, MN, Jackson County, MN, Martin County, MN, Nobles County, MN, Rock County, MN, Burt County, NE, Cedar County, NE, Colfax County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Knox County, NE, Pierce County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE, Aurora County, SD, Bon Homme County, SD, Clay County, SD, Davison County, SD, Douglas County, SD, Hanson County, SD, Hutchinson County, SD, Lincoln County, SD, McCook County, SD, Minnehaha County, SD, Turner County, SD, Union County, SD, Yankton County, SD
The radar
The Sioux Falls radar (KFSD), 140 km from the middle of the area, began a volume at 01:33 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
10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 30, 8:32 PM CDT | Tornado Warning | FSD | McCook | 33 min |
| May 30, 8:45 PM CDT | Tornado Warning | FSD | Hanson | 35 min |
| May 30, 9:04 PM CDT | Tornado Warning | FSD | McCook | 36 min |
| May 30, 9:20 PM CDT | Tornado Warning | FSD | Minnehaha | 50 min |
| May 30, 9:28 PM CDT | Tornado Warning | FSD | Turner | 32 min |
| May 30, 9:48 PM CDT | Severe Thunderstorm Warning | FSD | Lincoln | 32 min |
| May 30, 9:56 PM CDT | Tornado Warning | FSD | Lincoln | 24 min |
| May 30, 10:01 PM CDT | Severe Thunderstorm Warning | FSD | Lyon | 34 min |
| May 30, 10:08 PM CDT | Severe Thunderstorm Warning | FSD | Sioux | 32 min |
| May 30, 10:28 PM CDT | Severe Thunderstorm Warning | FSD | Nobles | 32 min |
The nearest sounding before it
Omaha, NE (KOAX), launched 00:00Z, 1.5 hours before the alert went out and 199 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
- 3693 J/kg
- Mixed-layer CIN
- -63 J/kg
- Mixed-layer LCL
- 1555 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 121 m²/s²
- 0-3 km storm-relative helicity
- 172 m²/s²
- Significant tornado parameter
- 1.3
- Supercell composite
- 21.7
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 31, 12:00 AM CDT | Tornado Watch | SPC | Allamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 20 more | 5 hr |
| May 30, 10:00 PM CDT | Tornado Watch | SPC | Anoka, Blue Earth, Brown, Carver, Chisago, Cottonwood and 30 more | 6 hr |
| May 30, 11:30 PM CDT | Severe Thunderstorm Watch | SPC | Dodge, Fillmore, Freeborn, Houston, Mower, Olmsted and 2 more | 6 hr |
Nearby
Tornado Watches in Iowa, 1998Tornado Watches in Nebraska, 1998Tornado Watches in South Dakota, 1998Every tornado watch in 1998
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.