Mesoscale Discussion 0241
NWS Storm Prediction Center Norman OK
0540 AM CDT Sun Mar 15 2026

Areas affected...Southeast MN...central/northern WI...and parts of
Upper MI

Concerning...Heavy snow 

Valid 151040Z - 151515Z

SUMMARY...Banded heavy snow with 1-2+ inch per hour rates will
continue spreading east-northeastward through the morning hours.

DISCUSSION...The latest mosaic radar data and surface observations
indicate banded heavy snow extending across parts of southern MN
into central WI, with the most intense portion of the band currently
focused over parts of southeastern MN. Over the next several hours,
the deep frontogenetic circulation and related mesoscale ascent that
is supporting these heavy snowfall rates will continue spreading
east-northeastward from southeastern MN across central/northern WI
and eventually into Upper MI. Given the strong/focused lift and
cold/deeply saturated profiles, an expansive area of 1 inch per hour
snowfall rates can be expected. Beneath the core of the more
organized banding, rates could exceed 2 inches per hour. Along the
southern fringes of the heavy snow, a substantial warm nose and
steep midlevel lapse rates/weak instability will continue to support
convective elements with mixed winter precipitation (freezing rain
and sleet) and widely scattered lightning flashes.

..Weinman.. 03/15/2026

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...MQT...GRB...DLH...ARX...MPX...

LAT...LON   43809266 43879340 44109384 44619405 45059370 45339295
            46528927 46778794 46738705 46558630 46298601 45828591
            45128644 44648734 44328864 44109003 43939132 43809266 

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0733 AM CDT Sun Mar 15 2026

Valid 151300Z - 161200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
THROUGH TONIGHT ACROSS PARTS OF THE MID SOUTH INTO LOWER OHIO VALLEY
AND ACROSS PARTS OF THE EASTERN GULF COAST STATES...

...SUMMARY...
Widespread strong to severe wind gusts may accompany a developing
squall line across and east of the mid/lower Mississippi Valley this
afternoon into this evening.  A couple of strong tornadoes are also
possible within and just ahead of this line across parts of the
lower Ohio Valley into Mid South and Gulf Coast regions.

...Mid Mississippi/Lower Ohio/Tennessee Valleys...
An active severe weather event is expected to occur this afternoon
through tonight over a large part of the east-central CONUS.  Water
vapor imagery confirms a powerful shortwave trough is amplifying
over the central Plains this morning, with a deep surface low
tracking from northern MO into Lower MI during this forecast period.
 Very strong southerly low-level winds (50-75 knots at 850mb) in the
warm sector will transport 50s surface dewpoints rapidly northward,
resulting in widespread marginal to moderate CAPE values from Lower
MI to the Gulf coast.  Current indications are that thunderstorms
will begin increasing in coverage and intensity around midday as a
strong cold front surges into the region.  The initial storms over
AR/MO will track into an environment quite favorable for supercell
structures and tornadoes - but the intense linear forcing along the
front, and weak capping ahead of the front may short-circuit
discrete cell formation and mesocyclone development.  Nevertheless,
a conditional risk of significant tornadoes will exist through at
least early evening.

There will be an increasing risk of widespread damaging winds and
occasional embedded tornadoes along the squall line/cold front as it
sweeps eastward into the OH and TN Valleys during the late afternoon
and evening.  Extremely strong winds just above the surface will
allow deep-convective elements to produce severe winds.  This threat
may persist much of the night, spreading as far east as eastern
KY/TN and much of GA by 16/12z.

Earlier model runs suggested the development of a more favorable
environment for supercells and tornadoes late tonight over parts of
AL/GA/FL.  More recent model solutions have backed off from that
scenario, but will keep the ENH for now and re-evaluate with 12z
model cycle.

..Hart/Weinman.. 03/15/2026