Alert archive / Iowa / Mesoscale Discussions in 2021
Mesoscale Discussion 2032
The Storm Prediction Center issued this mesoscale discussion at Dec 15, 2021, 4:51 PM CST for 5 states. It was in force for 114 min.
The area
The outline as issued.
The facts
- Issued
- Dec 15, 2021, 4:51 PM CST (22:51 UTC)
- Expired
- Dec 15, 2021, 6:45 PM CST
- In force
- 114 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch likely 563
- Chance of a watch
- 95%
All 59 counties
Allamakee County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Cedar County, IA, Chickasaw County, IA, Clayton County, IA, Clinton County, IA, Delaware County, IA, Des Moines County, IA, Dubuque County, IA, Fayette County, IA, Henry County, IA, Howard County, IA, Iowa County, IA, Jackson County, IA, Jefferson County, IA, Johnson County, IA, Jones County, IA, Keokuk County, IA, Lee County, IA, Linn County, IA, Louisa County, IA, Mitchell County, IA, Muscatine County, IA, Scott County, IA, Van Buren County, IA, Washington County, IA, Winneshiek County, IA, Henderson County, IL, Jo Daviess County, IL, Mercer County, IL, Rock Island County, IL, Dodge County, MN, Fillmore County, MN, Goodhue County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Rice County, MN, Steele County, MN, Wabasha County, MN, Winona County, MN, Clark County, MO, Scotland County, MO, Buffalo County, WI, Crawford County, WI, Grant County, WI, Iowa County, WI, Jackson 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), 137 km from the middle of the area, began a volume at 22:53 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
Davenport, (KDVN), launched 12:00Z, 10.9 hours before the alert went out and 158 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
- 2 J/kg
- Mixed-layer CIN
- -19 J/kg
- Mixed-layer LCL
- 566 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 351 m²/s²
- 0-3 km storm-relative helicity
- 358 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
934
ACUS11 KWNS 152251
SWOMCD
SPC MCD 152251
WIZ000-ILZ000-IAZ000-MNZ000-MOZ000-160045-
Mesoscale Discussion 2032
NWS Storm Prediction Center Norman OK
0451 PM CST Wed Dec 15 2021
Areas affected...central Iowa into far southern Minnesota
Concerning...Severe potential...Watch likely 563...
Valid 152251Z - 160045Z
Probability of Watch Issuance...95 percent
SUMMARY...A line of storms will continue to produce significant wind
damage, and may also produce several tornadoes as it rapidly moves
across Iowa, southern Minnesota and into southwest Wisconsin.
DISCUSSION...A surface low over northwest IA will continue to deepen
as it moves northeast into MN this evening. An ongoing line of
storms producing significant wind damage along the trailing cold
front is expected to remain intact as strong southerly winds warm
and destabilize the area downstream. While cool conditions currently
exist farther north into MN and WI, models suggest the warm front
will mix north, resulting in sufficient SBCAPE to support both wind
damage and tornadoes. Effective SRH of 500 m2/s2 is expected which
will support rotation regardless of storm mode.
..Jewell/Hart.. 12/15/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MKX...LSX...DVN...ARX...MPX...DMX...EAX...
LAT...LON 42709245 43339287 43919350 44289348 44639310 44729207
44689156 44409084 43949029 43428990 42678993 41909007
41039068 40299138 40229199 40349230 40639241 41309238
42279228 42709245SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 5:30 PM CST | Mesoscale Discussion | SPC | Adams | 90 min |
| Dec 15, 5:30 PM CST | Tornado Watch | SPC | Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more | 6 hr |
| Dec 15, 12:28 PM CST | Mesoscale Discussion | SPC | Adair, Adams, Appanoose, Audubon, Boone, Buena Vista and 59 more | 2 hr |
| Dec 15, 1:23 PM CST | Tornado Watch | SPC | Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 64 more | 7 hr |
| Dec 15, 3:55 PM CST | Mesoscale Discussion | SPC | Adair, Adams, Audubon, Boone, Buena Vista, Calhoun and 40 more | 95 min |
| Dec 15, 5:16 PM CST | Mesoscale Discussion | SPC | Adair, Adams, Audubon, Boone, Buena Vista, Calhoun and 30 more | 119 min |
| Dec 15, 2:29 PM CST | Mesoscale Discussion | SPC | Andrew, Bates, Buchanan, Caldwell, Cass, Clay and 10 more | 2 hr |
| Dec 15, 3:18 PM CST | Severe Thunderstorm Watch | SPC | Buchanan, Caldwell, Cass, Clay, Clinton, Daviess and 4 more | 5 hr |
| Dec 15, 5:01 PM CST | Mesoscale Discussion | SPC | Andrew, Barton, Bates, Benton, Buchanan, Caldwell and 31 more | 89 min |
Nearby
Mesoscale Discussions in Iowa, 2021Mesoscale Discussions in Wisconsin, 2021Mesoscale Discussions in Minnesota, 2021Every mesoscale discussion in 2021
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.