MD 0193 CONCERNING FREEZING RAIN FOR NORTHERN WI…WESTERN UPPER MI…EXTREME EAST-CENTRAL MN
Mesoscale Discussion 0193
NWS Storm Prediction Center Norman OK
0209 AM CST Sat Mar 05 2022
Areas affected...Northern WI...Western Upper MI...Extreme
east-central MN
Concerning...Freezing rain
Valid 050809Z - 051415Z
SUMMARY...Freezing rain will increase across northwest Wisconsin and
vicinity through the early morning, with hourly liquid-equivalent
rates of 0.05-0.10 inches per hour (or greater) possible.
DISCUSSION...At 08Z, light-to-moderate precipitation is increasing
across parts of northern WI, while convection (with heavier embedded
precipitation rates) is spreading northeastward toward the region
from eastern NE, western IA, and southern MN. This activity is
associated with a low-amplitude midlevel shortwave trough that is
ejecting northeastward in advance of a stronger shortwave currently
emerging across the southern Plains. Persistent low-level warm
advection and seasonably rich moisture (PW values of 0.5 to 0.8
inches) will continue to support substantial precipitation through
much of the overnight/early morning. The low-level warm advection
will also maintain a substantial warm nose in the 900-800 mb layer,
which will support mostly liquid precipitation types, though an
initial period of sleet or snow will be possible across far northern
WI into western Upper MI.
Several observations near the Twin Cities into northwest WI reported
hourly precipitation of 0.1-0.2 inches at 08Z. Liquid-equivalent
precipitation rates of 0.05-0.10 inches/hour (or greater) will
continue to be possible across the MCD area through the early
morning. Ice accretion rates will likely be greatest across parts of
northwest WI, where initial surface wet-bulb temperatures are colder
compared to more borderline conditions to the south and west, and
precipitation will likely be somewhat heavier compared to areas to
the northeast. Southern portions of the MCD area may eventually
change over to rain later this morning, as low-level warm advection
continues.
..Dean.. 03/05/2022
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MQT...GRB...DLH...ARX...MPX...
LAT...LON 45819301 46729221 46888937 46568840 45568820 44888903
44768966 44589019 44469146 44519228 44889292 45269315
45819301
