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fxus63 kdlh 180542 

Area forecast discussion
National Weather Service Duluth Minnesota
1142 PM CST sun Nov 17 2019

Short term...(this evening through Monday night)
issued at 331 PM CST sun Nov 17 2019

Pockets of drizzle or freezing drizzle are still possible this
evening in Iron, price, and Cook counties, but otherwise drier
conditions are expected overnight. Another weak system will move
through the region Monday afternoon into Tuesday which will bring
another bout of wintry mixed precipitation.

Overcast skies remain over the Northland this afternoon. Cloud
bases have gradually lifted, but remain low over portions of Iron,
price, and Cook counties. Those areas are most likely to
experience patchy drizzle or freezing drizzle for the next few
hours. Clouds will remain in place overnight and Monday with lows
tonight in the low 20s for north-central Minnesota and the middle
20s farther south.

Southerly flow aloft returns for Monday, but persistent cloud
cover will dampen the diurnal temperature trend. Highs will reach
the low 30s in the higher terrain of The Sawtooth mountains in the
Minnesota arrowhead and the upper 30s in central Minnesota east
into the St. Croix River Valley. Another shortwave trough will
move through the upper Mississippi River valley during the
afternoon and overnight hours. Deep saturation is expected, but
the thermal profile will be warm with a high and narrow dendritic
growth zone. Snow or drizzle will likely be the initial
precipitation type due to the presence of a warm layer aloft. Snow
ratios will be low with mainly columns and plates as the Crystal
habit. Much like todays system, we expect a loss of ice aloft
as subsidence erodes the cloud tops early Tuesday morning. There
should be enough lingering lift for a period of freezing drizzle.
Were not entirely confident in the loss of ice aloft given the
colder source region of the airmass and colder low- level
temperatures at the start of the event compared to today. As a
result, we have split the precipitation type into a mix of snow
and drizzle/freezing drizzle. Snow accumulations of up to an inch
are expected, with most locations seeing less than half an inch.
Ice accretion of up to five-hundredths of an inch are possible.

Long term...(tuesday through sunday)
issued at 331 PM CST sun Nov 17 2019

Tuesday the weak shortwave that brings some mixed precipitation
to the area Monday night continues to move slowly through the
area. Only some light snowfall accumulations are expected, along
with a possible thin glaze of ice. Like today, temperatures are
going to have a large effect on our precipitation type through the
day on Tuesday.

We have been focusing on the potential for a strong storm system
in the Wednesday-Thursday time frame. On Wednesday, it looks like
a leading shortwave will interact with the baroclinic zone draped
across the area, and should produce some light snowfall amounts
across the area during the daytime. We then have a stronger but
associated low pressure system will move across the area in the
Wednesday night to Thursday night time frame. While the models are
still not in very good agreement on this part of the storm, the
deterministic models we can see all develop a strong surface low
over eastern Colorado on Wednesday, move it northeast to near
southern Wisconsin by Thursday morning, then off into southern
Quebec by Friday morning. This low track is somewhat favorable for
getting some measurable precipitation into the forecast area. For
now, it appears there is potential for getting at least a few
inches of snow in the forecast area out of this storm, but we have
a lot of uncertainty in surface low track, what the thermal
profiles will look like, and a number of other uncertainties in
the track and strength of this storm. For now, am going to keep
mention of this storm in the severe weather potential statement on the vague side, and we can
refine as we get closer in to this storm.

The weather then gets relatively quiet for Friday and Saturday,
with a weak ridge overhead and a shortwave that appears to stay
north of the area for Saturday. Temperatures should be near
normals for both days. There is some potential for some
precipitation chances for Sunday, but do not have a lot of
confidence in it at this time. Temperatures should remain around
normal Sunday as well.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1142 PM CST sun Nov 17 2019

MVFR ceilings will persist through Sunday morning, then there is a
period of uncertainty where ceilings may either low to IFR or
partially clear out and briefly improve to VFR in the mid to late
morning hours Monday. For this set of tafs, based on experience
this time of year kept the forecast on the pessimistic side
leaning towards ceilings falling to IFR levels for a period of
time late Monday morning into the afternoon ahead of an
approaching warm front moving in from the west. In the late
afternoon into Monday night, MVFR to IFR ceilings will return (if
they don't already exist) with a period of light wintry precip
moving across terminals. This wintry precip could be either
rain/drizzle, freezing drizzle, or snow, with reductions in
visibility to IFR levels possible.

Winds light through the taf period, near calm this morning then
becoming southerly around 5 knots through Monday. Winds will then
veer to the west as the cold front associated with the
precipitation moves through Monday night.


issued at 1142 PM CST sun Nov 17 2019

No hazardous marine conditions expected through the next 48 hours.
Winds southwest to west around 5 to 10 knots at most through


Preliminary point temps/pops...
dlh 24 34 27 36 / 0 40 70 10
inl 22 35 28 35 / 10 60 70 30
brd 26 38 30 39 / 0 40 30 0
hyr 24 36 27 38 / 0 30 60 10
asx 27 36 27 39 / 20 30 60 10


Dlh watches/warnings/advisories...


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