684
FXUS63 KDLH 240522
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
1222 AM CDT Tue Sep 24 2024

.UPDATE...
Issued at 935 PM CDT Mon Sep 23 2024

Increased PoPs over my western counties again late this
evening. Area of rain showers along and behind the surface cold
front continues to propagate eastward and appeared to intensify
this evening. Several ASOS/AWOS sites over eastern ND and
eastern SD reported measurable precipitation with the showers.
Thus I have increased PoPs to a max of 60 percent over the next
4-6 hours as the front progresses eastward. There is still a
zone of 925 to 850 mb FGEN supporting upward vertical motion
ahead of the front. That band of FGEN along with a zone of
strong isentropic forcing for ascent will move into central and
north-central Minnesota later tonight. The 24.01Z RAP suggests
these forcing mechanisms will weaken Tuesday morning. Therefore
I continue to taper the showers down to sprinkles by 24.18Z.
Remainder of the forecast appears on track.

.PREV UPDATE...Issued at 535 PM CDT Mon Sep 23 2024

Increased PoPs slightly over central and north-central
Minnesota into the Arrowhead for tonight and Tuesday morning.
Precipitation has been reaching the ground associated with the
radar echoes over northwest Minnesota westward through central
North Dakota over the past several hours. QPE has been low, but
not zero. Webcams and automated stations reported light precip
under a band of 925 to 850 mb frontogenesis. Expect that zone of
ascent to propagate eastward along and behind a weak cool front
through tomorrow morning.

Changes to PoPs introduced "sprinkles" and a slight chance of
measurable rain to my western counties. Think the precip chances
will taper off by about 15Z Tuesday.

&&

.KEY MESSAGES...

- Fairly quiet weather this week with temperatures steadily
  warming back to well above normal.

- Next chance of widespread precipitation sometime next weekend
  or into next week.

&&

.DISCUSSION...
Issued at 228 PM CDT Mon Sep 23 2024

Much cooler temperatures have arrived along with a much drier
airmass. Some diurnal cumulus should dissipate quickly into the
evening hours while mid to high clouds continue to push into the
area. Another cool night is expected into Tuesday morning with
some patchy frost possible, but we`re currently not expecting it
to be widespread enough to need a Frost Advisory.

A shortwave lengthens across the Northern Plains overnight, pushing
a front across western Minnesota. Very dry air at the surface is
likely to prevent much in the way of precipitation from this system.
The rainiest solution from ensembles brings a trace to International
Falls and Brainerd and most models keep any precipitation from
falling. We`ve kept a 15% chance across our west, but rain is
unlikely.

As that shortwave becomes a cutoff low and falls southward, we`ll
see ridging return, with a gentle warm up hedging towards mid to
upper 70s mid to late week. This is still 10 to 20 degrees above
normal, but is not expected to be as hot and muggy as last week`s
heinous summer-like heat wave. A lack of precipitation, a dry
airmass, and clear skies should lead to good cool downs overnight.
Global ensembles bring back a widespread chance of precipitation
sometime next weekend into next week as a disturbance returns from
the Gulf of Mexico, but timing will be dependent on how fast the
ridge breaks down.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1220 AM CDT Tue Sep 24 2024

VFR conditions prevail for all terminals outside of the coastal
Arrowhead where IFR to MVFR prevails into Tuesday morning. A few
high-based showers are expected overnight for north-central
Minnesota as a very weak cool front slowly drags through the
state. Guidance is pointing to more widespread fog potential
building around 06Z Wed and afterward.

&&

.MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/...
Issued at 228 PM CDT Mon Sep 23 2024

No significant weather or winds expected over the next couple days.
Easterly winds become southerly overnight before a lake breeze
circulation Tuesday afternoon brings winds to become east to
northeasterly once again. Some gusts of 10-15 knots could be
possible at the head of the lake which may bring some chop to the
Twin Ports. Winds then turn to become southwesterly Wednesday.

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...None.

&&

$$

UPDATE...Huyck
DISCUSSION...Levens
AVIATION...NLy
MARINE...Levens