MD 0828 CONCERNING SEVERE THUNDERSTORM WATCH 257… FOR PARTS OF CENTRAL/NORTHEASTERN WISCONSIN INTO ADJACENT PORTIONS OF UPPER MICHIGAN
Mesoscale Discussion 0828
NWS Storm Prediction Center Norman OK
0546 PM CDT Sat May 18 2024
Areas affected…parts of central/northeastern Wisconsin into
adjacent portions of Upper Michigan
Concerning…Severe Thunderstorm Watch 257…
Valid 182246Z – 190045Z
The severe weather threat for Severe Thunderstorm Watch 257
continues.
SUMMARY…Strong to severe thunderstorm development, including a few
supercells posing a risk for severe hail and wind, probably will be
maintained while spreading eastward across the region through around
8-9 PM CDT.
DISCUSSION…Multiple discrete thunderstorms, including evolving
supercells, are ongoing, emanating from a zone of stronger
pre-frontal confluence across west central Wisconsin into the
western Upper Peninsula of Michigan vicinity. Boundary-layer
instability appears maximized along this corridor with mixed-layer
CAPE on the order of 1000-1500 J/kg and renewed convective
initiation remains possible another couple of hours as this zone
shifts slowly eastward.
Embedded within strongly sheared, 30-40 kt southwesterly deep-layer
mean flow, storms have tended to propagate northeastward and
eastward away from the initiating zone. Aided by the strong shear,
these storms may continue to pose a risk for severe hail and locally
strong gusts while spreading toward the Iron Mountain, Green Bay and
Oshkosh vicinities through 00-01Z. While forecast soundings exhibit
low-level hodographs potentially conducive to a a risk for
tornadoes, it still appears this risk will be limited by sizable
boundary-layer temperature/dew point spreads.
..Kerr.. 05/18/2024
…Please see www.spc.noaa.gov for graphic product…
ATTN…WFO…MQT…GRB…MKX…ARX…
LAT…LON 45868902 46428861 46008744 44678817 43778901 43609009
44288998 45358935 45868902
