Alert archive / Wisconsin / Mesoscale Discussions in 2021
Mesoscale Discussion 1591
The Storm Prediction Center issued this mesoscale discussion at Aug 24, 2021, 9:13 AM CDT for 9 counties in Wisconsin. It was in force for 62 min.
The area
The outline as issued.
The facts
- Issued
- Aug 24, 2021, 9:13 AM CDT (14:13 UTC)
- Expired
- Aug 24, 2021, 10:15 AM CDT
- In force
- 62 min
- Issued by
- the Storm Prediction Center
- Concerning
- Severe potential...watch unlikely
- Chance of a watch
- 20%
Counties Brown County, WI, Calumet County, WI, Menominee County, WI, Oconto County, WI, Outagamie County, WI, Shawano County, WI, Waupaca County, WI, Waushara County, WI, Winnebago County, WI
The radar
The Green Bay radar (KGRB), 30 km from the middle of the area, began a volume at 14:16 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
Green Bay/Straub, WI (KGRB), launched 12:00Z, 2.2 hours before the alert went out and 31 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
- 58 J/kg
- Mixed-layer CIN
- -344 J/kg
- Mixed-layer LCL
- 1387 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- -33 m²/s²
- 0-3 km storm-relative helicity
- 55 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
819
ACUS11 KWNS 241413
SWOMCD
SPC MCD 241413
WIZ000-241515-
Mesoscale Discussion 1591
NWS Storm Prediction Center Norman OK
0913 AM CDT Tue Aug 24 2021
Areas affected...eastern Wisconsin
Concerning...Severe potential...Watch unlikely
Valid 241413Z - 241515Z
Probability of Watch Issuance...20 percent
SUMMARY...Threat for a few strong to severe gusts will persist
across a part of eastern Wisconsin until about 16Z. Overall
magnitude and spacial extent of the threat does not appear to
warrant a WW at this time.
DISCUSSION...A line of storms along the eastern periphery of a large
MCS is moving east at 35 kt through central WI. These storms are
tracking along the instability gradient associated with a reservoir
of moderate instability (2000 J/kg MLCAPE) which extends from
southern WI through central and southern Lake Michigan. Overall
tendency has been for storms to undergo some weakening. However, as
the downstream boundary layer warms, some re-intensification is
possible before activity moves offshore.
..Dial/Kerr.. 08/24/2021
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...GRB...MKX...
LAT...LON 44078928 44678900 45268861 45258785 44648752 43878776
43798856 44078928SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 24, 2:17 AM CDT | Severe Thunderstorm Watch | SPC | Pierce, Polk, Saint Croix | 7 hr |
| Aug 24, 3:00 AM CDT | Mesoscale Discussion | SPC | Pierce, Polk, Saint Croix | 2 hr |
| Aug 24, 6:00 AM CDT | Mesoscale Discussion | SPC | Adams, Buffalo, Clark, Columbia, Crawford, Dane and 26 more | 90 min |
| Aug 24, 7:10 AM CDT | Mesoscale Discussion | SPC | Adams, Barron, Buffalo, Chippewa, Clark, Dunn and 15 more | 95 min |
| Aug 24, 12:44 PM CDT | Mesoscale Discussion | SPC | Crawford, Grant, Iowa, Richland, Sauk, Vernon | 91 min |
| Aug 24, 1:52 PM CDT | Severe Thunderstorm Watch | SPC | Grant | 5 hr |
| Aug 24, 3:09 PM CDT | Mesoscale Discussion | SPC | Green, Rock, Walworth | 66 min |
| Aug 24, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | Green, Lafayette, Rock, Walworth | 5 hr |
Nearby
Mesoscale 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.