QPFHSD

Probabilistic Heavy Snow and Icing Discussion
NWS Weather Prediction Center College Park MD
330 AM EDT Thu Apr 2 2026

Valid 12Z Thu Apr 02 2026 - 12Z Sun Apr 05 2026

...Northern Plains through the Great Lakes... Day 1...

...First of back-to-back systems will bring significant late-
season snow and freezing rain with substantial impacts...

The first in a pair of powerful late-season winter storms will
continue to develop as an amplifying, negatively-tilted trough
lifts northeast from the central Plains this morning. This system
is expected to continue its northeastward track, reaching the upper
Mississippi Valley and western Great Lakes by this evening before
lifting into western Ontario by early tomorrow. Fueled by both Gulf
and Pacific moisture, this system is expected to produce a lengthy
stripe of significant ice, bordered by heavy snow to the north.

Supported by a warm nose of air aloft, snow transitioning to sleet
and freezing rain is expected from eastern South Dakota to
northern Michigan. Significant ice accumulations are likely for
portions of the region, especially over parts of northern Wisconsin
and Michigan. WPC guidance continues to show probabilities greater
than 70 percent for ice accumulations over 0.10 inch, along with a
greater than 50 percent chance for ice accumulations over 0.25
inch over parts of the region through early Friday.

The better chance for heavier snow will center to the north across
the Minnesota Arrowhead, where WPC probabilities show a greater
than 70 percent chance for snow accumulations over 4 inches.

Key Messages are in effect for this system and are linked
below (Key Messages #1).

...Northern New York and New England... Days 1-3...

Moisture from the first Midwest storm will surge into New England
tonight. Cold air anchored by Canadian high pressure will initially
support snow before a transition to a wintry mix occurs.

Northern Maine is likely to see the longest period of snow, with
snow rates of 1 in/hr possible Thursday night into Friday.
WPC probabilities greater than 50 percent for snow accumulations
over 4 inches are largely confined to far northern Aroostook
County. But even areas this far north are expected to eventually
transition from snow to sleet and freezing rain.

Further to the south, from the Adirondacks to the northern New
England mountains, a wintry mix with accumulating ice is more
likely. Significant ice accumulations are most likely from the
White Mountains into northwestern Maine, where WPC probabilities
show a 50-70+ percent chance for ice accumulations over 0.10 inch
through midday Friday.

As the second system to impact the Midwest lifts northeast, a
second round of snow and ice is expected Saturday night into
Sunday, with most areas quickly transitioning from snow to sleet
and freezing rain.

...Pacific Northwest through Northern/Central Rockies... Day 1...

A deep, cold low will continue to move inland over the Northwest
this morning, bringing additional snow to the Cascades as the
leading edge spreads into the northern Rockies.

Continued onshore flow in the wake of the system will bring
additional heavy snow to parts of the Cascades as snow levels
plunge behind a sharp cold cold front pressing south and east.

Snow is expected to wane across the Northwest by this evening, but
continue across parts of the northern and central Rockies as the
low moves across the region late today into early Friday.

The heaviest snow accumulations through early Friday are expected
to focus along the northern Rockies from western Montana to
northern Utah. WPC probabilities indicate widespread accumulations
of 6+ inches are likely, with some potential for amounts over a
foot in the higher terrain.

...Northern Plains to the Upper Midwest... Days 2-3...

...Second of back-to-back systems expected to bring additional
heavy snow and icing to portions of the region late week...

As the previously described low moves east of the Rockies, a second
surface low will strengthen over the Central Plains and lift
northeast into the Upper Midwest, bringing a renewed round of
heavy banded snow and ice to the Northern Plains and the Upper Midwest.

Strong lift supported in part by coupled upper jet forcing will
support snowfall rates of 1-2 in/hr across the Northern Plains.
Guidance indicates a more expansive footprint of heavy snow is
likely with this second system. WPC probabilities indicate snow
totals exceeding 8 inches are likely from southeastern North
Dakota and northeastern South Dakota to northern Minnesota. Within
this area some locations may see a foot or more, with southeastern
South Dakota the focus for the highest probabilities in the latest
WPC guidance.

This storm is expected to deliver another round of freezing rain
to portions of the region as well. Once again, parts of northern
Wisconsin and Michigan may be affected by the heaviest ice
accumulations, compounding impacts generated by the first storm.

Key Messages are in effect for this system and are linked
below (Key Messages #2).

Pereira

...Winter Storm Key Messages are in effect. Please see current
Key Messages below...

https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_1.png

https://www.wpc.ncep.noaa.gov/key_messages/LatestKeyMessage_2.png


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