017
FXUS63 KDLH 231737
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1137 AM CST Sun Feb 23 2025

.KEY MESSAGES...

- Warm temperatures are expected for the next several days with
  high temperatures increasing above freezing for most
  locations.

- A light wintry mix is likely this evening through tonight, especially
  in the MN Arrowhead. This could lead to slippery roads due to
  light snow and ice accumulations.

- An active pattern will persist this upcoming week with chances
  for light wintry mix on Tuesday night into Wednesday as well
  as Friday into Saturday morning.

&&

.DISCUSSION...
Issued at 416 AM CST Sun Feb 23 2025

Conditions early this morning has been relatively quiet, even as a
500mb shortwave trough propagates through. This shortwave will pass
through the CWA mostly dry, despite light reflectivity currently
being observed by KDLH and surrounding radars. Hi-res model
soundings show a sizable amount of low-level dry air from around
800mb to the sfc, which is expected to largely inhibit flurry
and/or light snow development this morning. As the shortwave
continues to propagate farther east, increased low-level
saturation in northwest WI will create the potential for
scattered flurries this morning. Overall snow amounts are
expected to be only around a dusting this morning. In addition
to flurries, patchy fog will be possible early this morning as
skies briefly clear behind the shortwave trough axis.

Southerly flow creating WAA following this morning`s shortwave
passage combined with peaks of sun through the clouds will create
warm conditions today, with a 95+% chance for high temps today
exceeding 32 degrees for the vast majority of the CWA. Diurnal
heating today is also expected to be aided by the decreased albedo
in the CWA resulting from tree cover. Expect cloud cover to increase
this afternoon as another shortwave approaches the CWA.

This second shortwave and associated sfc low pressure arriving this
evening into tonight will bring a chance for rain, snow, and
freezing rain with the heaviest precip occurring in the Arrowhead
and Bayfield Peninsula. The lion`s share of QPF associated with this
low pressure system is expected to remain north of the border in
Ontario. However, there is a 60% chance for around 0.10" or more of
QPF in the Arrowhead northeast of US-53 as mid to low-level
saturation briefly occurs. Expect lesser amounts of QPF farther
south and west. Precipitation type will be fairly messy this evening
through tonight as temperatures aloft and at the sfc flirt within a
few degrees of freezing, especially in Lake and Cook Counties. The
general trend of precip types in the Arrowhead will be an initial
wintry mix of rain and snow shifting to an hour or two of freezing
rain before returning to a wintry mix.

Overall accumulations of both snow and ice are expected to be light
from tonight`s system due to low QPF amounts, a short period of time
for favorable FZRA thermodynamics, and low SLR around 6:1 to 8:1.
Global ensemble members from the GFS and ECMWF are in fairly decent
agreement regarding snow amounts tonight through tomorrow, with
total snow being less than an inch in tip the Arrowhead. As for ice
amounts, accumulations may be up to several hundredths. While
overall amounts of snow and ice accumulations this evening through
tonight will be light, use caution as roads may be slippery.

After the shortwave moving through tonight departs downstream on
Monday, a dynamic pattern aloft will continue through this
upcoming week with periods of wintry precip and quiet weather as
several shortwave troughs propagate through followed by brief
periods of ridging. Precip chances in this active pattern coming
up this week will be on Tuesday night into Wednesday morning as
well as Friday into Saturday morning. Temperatures will remain
fairly warm this upcoming week with highs increasing above
freezing and lows decreasing to the 20s and low 30s. Snow
amounts this upcoming week will be fairly light due to a
combination of fairly warm temperatures and a lack of deep
moisture advection into the CWA.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1137 AM CST Sun Feb 23 2025

Low MVFR to near-IFR stratus continue at DLH/HIB until around
19Z before shifting northeast of these terminals into the tip of
the Arrowhead. Otherwise, expect VFR conditions for the area
much of this afternoon into early evening under increasing mid
and high level clouds from the west. Low pressure tracking east
through northern Manitoba and Ontario will bring predominately
rain for most of the area this evening and tonight, with the
exception being light FZRA and -SN primarily north and east of
DLH/HIB/INL. With that said, can`t completely rule out a
rain/snow mix at all terminals aside from BRD, with the best
potential, around a 30 percent chance, at HIB/DLH/INL.

Gusty southwest winds develop later this afternoon and evening,
and then turn westerly tonight through the end of the TAF
period. Increasing winds aloft will also lead to LLWS this
evening into early Monday morning.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 416 AM CST Sun Feb 23 2025

Initially light and variable winds this morning will become
southerly for all areas by this evening with speeds of 15 knots or
less. Expect winds to increase tonight out of the southwest, 10 to
20 knots with higher gusts of 25 to 30 knots. Small Craft Advisories
remain in effect through Monday afternoon for all of western Lake
Superior as those southwesterly winds linger into the early
afternoon. Expect waves to also build, especially in the outer
Apostle Islands and North Shore from Taconite Harbor to Grand
Portage.

For the open water discussion, refer to the NWS Marquette Area
Forecast Discussion at weather.gov/mqt.

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
MARINE...Small Craft Advisory from 10 PM this evening to 4 PM CST
     Monday for LSZ140>146-148-150.

&&

$$

DISCUSSION...Unruh
AVIATION...Rothstein
MARINE...Unruh