Alert archive / Minnesota / Mesoscale Discussions in 2021
Mesoscale Discussion 1608
The Storm Prediction Center issued this mesoscale discussion at Aug 26, 2021, 10:43 AM CDT for 7 counties in Minnesota; Brookings County, Deuel County, Moody County, South Dakota. It was in force for 92 min.
The area
The outline as issued.
The facts
- Issued
- Aug 26, 2021, 10:43 AM CDT (15:43 UTC)
- Expired
- Aug 26, 2021, 12:15 PM CDT
- In force
- 92 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 463
Counties Lac qui Parle County, MN, Lincoln County, MN, Lyon County, MN, Murray County, MN, Pipestone County, MN, Redwood County, MN, Yellow Medicine County, MN, Brookings County, SD, Deuel County, SD, Moody County, SD
The radar
The Sioux Falls radar (KFSD), 108 km from the middle of the area, began a volume at 15:45 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
Aberdeen, SD (KABR), launched 12:00Z, 3.7 hours before the alert went out and 189 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
- 1092 m above ground
- 0-6 km bulk shear
- 62 kt
- 0-1 km storm-relative helicity
- 365 m²/s²
- 0-3 km storm-relative helicity
- 490 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.4
The text
As transmitted.
670
ACUS11 KWNS 261544
SWOMCD
SPC MCD 261543
MNZ000-SDZ000-261715-
Mesoscale Discussion 1608
NWS Storm Prediction Center Norman OK
1043 AM CDT Thu Aug 26 2021
Areas affected...Extreme east-central SD into southwest MN
Concerning...Severe Thunderstorm Watch 463...
Valid 261543Z - 261715Z
The severe weather threat for Severe Thunderstorm Watch 463
continues.
SUMMARY...A swath of damaging winds is possible over the next 1-2
hours as an intense MCS moves eats-southeastward.
DISCUSSION...A well-organized MCS has recently produced a 63 kt gust
at Huron, SD and a 65 kt gust at Watertown, SD. While the convection
remains somewhat elevated, a strong cold pool and pressure
perturbation has been noted in surface observations, with 2-hr
pressure rises in excess of 5 mb noted across northeast SD as the
line passed through, and 2-hr pressure falls of 3-5 mb further west,
where an apparent wake low has maintained strong surface winds at
KABR well after the passage of the storms.
While heating downstream of the MCS is being limited by cloudiness
associated with a downstream thunderstorm cluster across Iowa,
continued low-level moisture transport and MUCAPE in excess of 1500
J/kg should maintain the system in the short term, with a
substantial damaging wind threat spreading into portions of
southwest MN over the next 1-2 hours.
..Dean.. 08/26/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MPX...FSD...ABR...
LAT...LON 45049658 45059611 45019573 44789523 44459511 44159529
43989550 43849603 43889668 44009709 44159720 45049658SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 26, 8:36 AM CDT | Mesoscale Discussion | SPC | Big Stone, Lac qui Parle | 84 min |
| Aug 26, 9:05 AM CDT | Severe Thunderstorm Watch | SPC | Big Stone, Chippewa, Kandiyohi, Lac qui Parle, Lincoln, Lyon and 11 more | 4 hr |
| Aug 26, 1:12 PM CDT | Mesoscale Discussion | SPC | Fillmore, Houston, Winona | 93 min |
| Aug 26, 1:53 PM CDT | Mesoscale Discussion | SPC | Carver, Dakota, Goodhue, Hennepin, Le Sueur, Ramsey and 3 more | 97 min |
| Aug 26, 2:35 AM CDT | Mesoscale Discussion | SPC | Brown, Campbell, Corson, Dewey, Edmunds, Faulk and 6 more | 2 hr |
| Aug 26, 3:10 AM CDT | Mesoscale Discussion | SPC | Bon Homme, Charles Mix, Clay, Hutchinson, Turner, Yankton | 3 hr |
| Aug 26, 5:34 PM CDT | Mesoscale Discussion | SPC | Clay, Lincoln, Turner, Union, Yankton | 116 min |
Nearby
Mesoscale Discussions in Minnesota, 2021Mesoscale Discussions in South Dakota, 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.