Alert archive / Iowa / Mesoscale Discussions in 2017
Mesoscale Discussion 496
The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2017, 4:01 PM CDT for 5 states. It was in force for 119 min.
The area
The outline as issued.
The facts
- Issued
- Apr 15, 2017, 4:01 PM CDT (21:01 UTC)
- Expired
- Apr 15, 2017, 6:00 PM CDT
- In force
- 119 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 40%
All 84 counties
Adair County, IA, Adams County, IA, Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cerro Gordo County, IA, Cherokee County, IA, Clarke County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Dickinson County, IA, Emmet County, IA, Franklin County, IA, Fremont 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, Kossuth County, IA, Lyon County, IA, Madison County, IA, Mills County, IA, Monona County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Polk County, IA, Pottawattamie County, IA, Ringgold County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Story County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Webster County, IA, Winnebago County, IA, Woodbury County, IA, Wright County, IA, Faribault County, MN, Jackson County, MN, Martin County, MN, Atchison County, MO, Holt County, MO, Nodaway County, MO, Worth County, MO, Burt County, NE, Cass County, NE, Cedar County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Sarpy County, NE, Saunders County, NE, Stanton County, NE, Thurston County, NE, Washington County, NE, Wayne County, NE, Clay County, SD, Lincoln County, SD, Union County, SD
The radar
The Omaha radar (KOAX), 61 km from the middle of the area, began a volume at 21:01 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, 9.0 hours before the alert went out and 61 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1748 m above ground
- 0-6 km bulk shear
- 40 kt
- 0-1 km storm-relative helicity
- -29 m²/s²
- 0-3 km storm-relative helicity
- -118 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 15, 5:05 PM CDT | Severe Thunderstorm Watch | SPC | Adair, Adams, Audubon, Boone, Calhoun, Carroll and 35 more | 7 hr |
| Apr 15, 5:06 PM CDT | Mesoscale Discussion | SPC | Cedar, Clayton, Clinton, Delaware, Dubuque, Henry and 10 more | 84 min |
| Apr 15, 6:22 PM CDT | Mesoscale Discussion | SPC | Cherokee, Monona, Plymouth, Woodbury | 83 min |
| Apr 14, 8:37 PM CDT | Mesoscale Discussion | SPC | Arthur, Banner, Cheyenne, Deuel, Garden, Keith and 3 more | 113 min |
| Apr 14, 9:17 PM CDT | Mesoscale Discussion | SPC | Adams, Boone, Buffalo, Butler, Clay, Colfax and 31 more | 88 min |
Nearby
Mesoscale Discussions in Iowa, 2017Mesoscale Discussions in Nebraska, 2017Mesoscale Discussions in Missouri, 2017Every mesoscale discussion in 2017
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.