Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 031745

Area Forecast Discussion
National Weather Service Duluth MN
1245 PM CDT Mon Oct 3 2022

.DISCUSSION...(Today through Sunday)
Issued at 424 AM CDT Mon Oct 3 2022

Summary...A few more days of seasonably warm weather will come to
an end Wednesday with a cold front that brings higher chances of
rain and a period of colder temperatures with some of that white
stuff flying through the air Wednesday night and Thursday.

Weakly forced precipitation can be the bane of a weather
forecasters existence, as it is hard to determine exactly what is
driving the location of precipitation, the models have a poor
handle on it, making a normally good consensus blend almost
worthless. Experience says that instead of trying to get overly
detailed with the location of pops today and tonight before the
stronger forcing moves in for Tuesday and Wednesday have broad
brushed small pops, mainly over northern MN within the plume of
warm air advection and weak frontogenesis bands that are moving
across the region. The warm air advection will help temperatures
to rise into the upper 60s and low 70s despite the mostly cloudy
skies both Monday and Tuesday.

A big change in the weather arrives on Wednesday and Wednesday
night, with a strong cold front pushing through the area along
with a strong upper level shortwave and vort max that dives in
Wednesday night. Of note with this system is the large pool of
cold temperatures aloft that makes the front rather strong and
dynamics along it significant. We have mostly chance pops going
for Wednesday and Wednesday night right now, but would not be
surprised to need to boost these as the models converge on timing.
With the strength of the cold pool aloft (-8C) and the surface
water temperatures around 57F/14C, I expect some lake effect
showers along the south shore Thursday and Thursday night, so have
increased pops for those periods for the Bayfield peninsula on
east. The strong cold air advection, tight pressure gradient,
steep low level lapse rates and 25 to 30 knot winds aloft should
mix down to the surface for much of Thursday, and I have boosted
consensus winds from late Wednesday night through most of Thursday
before diminishing Thursday night. This system will bring a
couple days of colder than normal temperatures with the cold pool
aloft, north winds and weak ridging settling in to help produce
good radiational cooling at night. Highs both Thursday and Friday
should only be in the 40s, even if we can get some sunshine, and
at night we should have some more frosty temps both nights.

Moderation can be expected into the weekend even as we remain in
a northwest flow pattern aloft. As the cold pool retreats farther
east on Saturday warmer temperatures moving in at the mid levels
should allow our temperatures to warm back towards normal for the
weekend. Weak ridging at the surface should help keep
precipitation chances small as well. The models are hinting at a
shortwave moving across the area sometime over the weekend, but
there is very poor consensus on timing and track of this and
confidence in any associated precipitation chances is very low.


.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 1232 PM CDT Mon Oct 3 2022

VFR with plenty of high clouds crossing as a frontal system moves
our way through the Dakotas. There are spotty showers out there,
but not enough to warrant even a VCSH in TAFs. Winds are going to
be fairly steady from the south at 10 gusting to 15.


Issued at 424 AM CDT Mon Oct 3 2022

South to southwest winds of 10 to 15 knots with a few gusts
approaching 20 knots during the afternoon hours today will
diminish to around 10 knots overnight tonight before increasing
again for Tuesday, with a similar pattern continuing through
Wednesday. Waves should be generally less than 3 feet through
Wednesday. A strong cold front is expected to move across the
lake Wednesday night/Thursday, which will be followed by a period
of strong northwest winds on Thursday. Gales may be possible, but
we are definitely expecting hazardous conditions for small craft,
mainly on Thursday.


DLH  70  55  69  53 /  20  20  20  20
INL  70  52  69  50 /  30  20  30  20
BRD  72  56  70  52 /  10  20  20  20
HYR  71  52  71  51 /  30  20  10  20
ASX  74  55  74  54 /  50  10  10  20




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