Alert archive / Minnesota / Mesoscale Discussions in 2021
Mesoscale Discussion 1817
The Storm Prediction Center issued this mesoscale discussion at Oct 9, 2021, 8:27 PM CDT for 10 counties in Minnesota. It was in force for 93 min.
The area
The outline as issued.
The facts
- Issued
- Oct 9, 2021, 8:27 PM CDT (01:27 UTC)
- Expired
- Oct 9, 2021, 10:00 PM CDT
- In force
- 93 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe thunderstorm watch 514...515
Counties Becker County, MN, Douglas County, MN, Grant County, MN, Otter Tail County, MN, Pope County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Wadena County, MN, Wilkin County, MN
The radar
The Fargo/Grand Forks radar (KMVX), 184 km from the middle of the area, began a volume at 01:28 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 00:00Z, 1.5 hours before the alert went out and 233 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
- 1552 m above ground
- 0-6 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 131 m²/s²
- 0-3 km storm-relative helicity
- 150 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
339
ACUS11 KWNS 100127
SWOMCD
SPC MCD 100127
MNZ000-NDZ000-100300-
Mesoscale Discussion 1817
NWS Storm Prediction Center Norman OK
0827 PM CDT Sat Oct 09 2021
Areas affected...Southeast ND...West-Central MN
Concerning...Severe Thunderstorm Watch 514...515...
Valid 100127Z - 100300Z
The severe weather threat for Severe Thunderstorm Watch 514, 515
continues.
SUMMARY...Damaging winds will accompany a squall line as it races
northeast this evening.
DISCUSSION...Well-organized squall line has evolved and is surging
northeast across the remainder of ww514 into the western portions of
ww515. An MCV has evolved over the northwestern portion of a larger
complex of storms over southeast ND, well north of the primary
surface low. The apex of a larger bow is racing east-northeast
across Douglas County MN, and should advance across Alexandria very
shortly. Damaging winds in excess of 50-60kt is likely noted at
times with this squall line. Strong low-level warm advection is
focused across west-central/central MN this evening as 45kt LLJ is
feeding this surging line. Current thinking is the squall line will
continue to propagate across the remainder of ww515 over the next
several hours, primarily affecting the northwestern two-thirds of
the watch.
..Darrow.. 10/10/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...DLH...MPX...FGF...ABR...
LAT...LON 46579713 47009579 46429448 45409503 45189617 45909627
46579713SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 9, 11:20 PM CDT | Mesoscale Discussion | SPC | Benton, Cass, Chippewa, Crow Wing, Kandiyohi, Lac qui Parle and 7 more | 115 min |
| Oct 10, 12:57 PM CDT | Mesoscale Discussion | SPC | Itasca, Koochiching, Lake, Lake of the Woods, Saint Louis | 2 hr |
| Oct 10, 1:42 PM CDT | Severe Thunderstorm Watch | SPC | Cook, Itasca, Koochiching, Lake, Saint Louis | 7 hr |
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.