Alert archive / Iowa / Mesoscale Discussions in 2021
Mesoscale Discussion 152
The Storm Prediction Center issued this mesoscale discussion at Mar 10, 2021, 5:43 PM CST for 27 counties in Iowa; 10 counties in Minnesota; 5 counties in Wisconsin. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 10, 2021, 5:43 PM CST (23:43 UTC)
- Expired
- Mar 10, 2021, 7:45 PM CST
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Tornado watch 16
All 42 counties
Allamakee County, IA, Benton County, IA, Black Hawk County, IA, Bremer County, IA, Buchanan County, IA, Butler County, IA, Cerro Gordo County, IA, Chickasaw County, IA, Fayette County, IA, Floyd County, IA, Franklin County, IA, Grundy County, IA, Hardin County, IA, Howard County, IA, Jasper County, IA, Lucas County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Mitchell County, IA, Polk County, IA, Poweshiek County, IA, Story County, IA, Tama County, IA, Warren County, IA, Winneshiek County, IA, Worth County, IA, Dodge County, MN, Fillmore County, MN, Freeborn County, MN, Goodhue County, MN, Houston County, MN, Mower County, MN, Olmsted County, MN, Steele County, MN, Wabasha County, MN, Winona County, MN, Buffalo County, WI, Dunn County, WI, Pepin County, WI, Pierce County, WI, Trempealeau County, WI
The radar
The Des Moines radar (KDMX), 154 km from the middle of the area, began a volume at 23:42 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 nearest sounding before it
Minneapolis, MN (KMPX), launched 12:00Z, 11.7 hours before the alert went out and 222 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
- 946 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 76 m²/s²
- 0-3 km storm-relative helicity
- 219 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
239
ACUS11 KWNS 102344
SWOMCD
SPC MCD 102343
IAZ000-WIZ000-MNZ000-110145-
Mesoscale Discussion 0152
NWS Storm Prediction Center Norman OK
0543 PM CST Wed Mar 10 2021
Areas affected...southeastern Minnesota/west-central
Wisconsin/central and eastern Iowa
Concerning...Tornado Watch 16...
Valid 102343Z - 110145Z
The severe weather threat for Tornado Watch 16 continues.
SUMMARY...Risk for isolated damaging wind gusts, and a tornado or
two, remain possible in/near Tornado Watch 16.
DISCUSSION...Latest radar loop shows a cluster of storms -- which
have exhibited radar rotational signatures at times -- just
east/southeast of the Minneapolis/St. Paul metro area, moving
northeastward at around 40 kt. The storms are ongoing near the
southwest-to-northeast warm front lying across this area, on the
very northern fringe a appreciable instability. Given storm motion
roughly along the vorticity-rich warm front, an additional tornado
or two will remain possible over the next 1 to 2 hours.
Farther south, convection has been slower to organize -- in part due
to weak CAPE. Still, shear remains quite favorable across the area,
which has permitted a few stronger storms to evolve over the past
hour -- particularly over south central Iowa. Though CAPE should
remain a limiting factor -- particularly as the airmass cools
diurnally, available shear will support isolated stronger storms --
capable of gusty/damaging winds and possibly a tornado -- over the
next few hours.
..Goss.. 03/10/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DVN...ARX...MPX...DMX...
LAT...LON 41389392 42389327 43529349 44529321 44879282 45109190
44949133 43429127 41709205 41119275 40949369 41389392SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 10, 1:32 PM CST | Mesoscale Discussion | SPC | Adair, Audubon, Benton, Black Hawk, Boone, Bremer and 38 more | 118 min |
| Mar 10, 2:46 PM CST | Tornado Watch | SPC | Allamakee, Benton, Black Hawk, Boone, Bremer, Buchanan and 28 more | 5 hr |
Nearby
Mesoscale Discussions in Iowa, 2021Mesoscale Discussions in Minnesota, 2021Mesoscale Discussions in Wisconsin, 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.