Alert archive / Minnesota / Mesoscale Discussions in 2021
Mesoscale Discussion 1335
The Storm Prediction Center issued this mesoscale discussion at Jul 23, 2021, 7:44 PM CDT for 5 counties in Minnesota. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 23, 2021, 7:44 PM CDT (00:44 UTC)
- Expired
- Jul 23, 2021, 9:45 PM CDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 387
Counties Aitkin County, MN, Carlton County, MN, Cass County, MN, Lake County, MN, Saint Louis County, MN
The radar
The Duluth radar (KDLH), 47 km from the middle of the area, began a volume at 00:43 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
International Fa, MN (KINL), launched 00:00Z, 0.7 hours before the alert went out and 163 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
- 114 J/kg
- Mixed-layer CIN
- -292 J/kg
- Mixed-layer LCL
- 1627 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 171 m²/s²
- 0-3 km storm-relative helicity
- 236 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
490
ACUS11 KWNS 240045
SWOMCD
SPC MCD 240044
MNZ000-WIZ000-240245-
Mesoscale Discussion 1335
NWS Storm Prediction Center Norman OK
0744 PM CDT Fri Jul 23 2021
Areas affected...northern Minnesota
Concerning...Severe Thunderstorm Watch 387...
Valid 240044Z - 240245Z
The severe weather threat for Severe Thunderstorm Watch 387
continues.
SUMMARY...A few reports of severe hail and wind remain possible into
the Arrowhead of Minnesota.
DISCUSSION...Strong to severe cells currently extend from Cass
County to Lake County MN, the latter being the largest storm with a
relatively fast southeastward motion and possible wind threat. Other
cells to the west may contain marginally severe hail.
Southwesterly low-level winds of 25kt as seen on 00Z MPX sounding
will maintain theta-e advection ahead of these storms, and further
congealing of convection is possible. Storms may persist for several
hours given further height falls this evening. Although CIN will
gradually increase with time, new development along outflows or
southwestern flanks of the existing storms is possible in the near
term as the air mass remains relatively uncapped.
..Jewell.. 07/24/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...
LAT...LON 46689199 46479372 46639427 46959453 47189432 47249356
47689263 48059135 47999061 47659037 47189117 46689199SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 23, 9:07 PM CDT | Mesoscale Discussion | SPC | Lac qui Parle, Lincoln, Lyon, Murray, Pipestone, Redwood and 2 more | 2 hr |
| Jul 23, 10:33 PM CDT | Mesoscale Discussion | SPC | Big Stone, Clay, Grant, Otter Tail, Stevens, Traverse and 1 more | 117 min |
| Jul 23, 11:22 PM CDT | Severe Thunderstorm Watch | SPC | Anoka, Benton, Big Stone, Chippewa, Douglas, Grant and 16 more | 4 hr |
| Jul 24, 1:10 AM CDT | Mesoscale Discussion | SPC | Big Stone, Chippewa, Douglas, Grant, Kandiyohi, Meeker and 9 more | 95 min |
Nearby
Mesoscale 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.