Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 091818 AAD

Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
1218 PM CST Sat Dec 9 2017

Issued at 1219 PM CST Sat Dec 9 2017

Update for new 18Z Aviation Discussion below.

UPDATE Issued at 1101 AM CST Sat Dec 9 2017

Extended winter weather advisory across northern Ashland and Iron
counties through 21Z this afternoon. Looking at the short term
models, satellite images, and current obs indicate the northerly
winds will continue before switching direction by late afternoon.

UPDATE Issued at 946 AM CST Sat Dec 9 2017

Breaks in the clouds in the twin ports and along the north shore
at forecast issuance time. Satellite does indicate clouds starting
to fill in and will continue to fill in rest of the morning. The
rest of the day should be mostly cloudy and will put in flurries
across the forecast area. Rest of forecast unchanged.


.SHORT TERM...(Today through Sunday)
Issued at 303 AM CST Sat Dec 9 2017

Still a few snow shower bands showing up on radar, but overall a
decrease in shower activity as weak high pressure builds today.
Another weak short wave will brush the arrowhead with light snow
again tonight though no snowfall accumulation is expected. High
pressure builds again on Sunday for another break between short

No real concerns, but wind chills this morning in Cook County
will approach -20 F.

.LONG TERM...(Sunday night through Friday)
Issued at 303 AM CST Sat Dec 9 2017

This week will feature a series of weak Canadian Clippers
bringing light snow to the Northland. The first two Clippers, one
early in the week and the other in the middle of the week, will
bring a usual blast of Arctic air. Temperatures will be near or
below normal, with the coldest stretch of weather Monday into

A Canadian Clipper will likely track from the Canadian Prairies
through northern Minnesota Sunday night and through western and
southern Wisconsin Monday. The good agreement between the 00Z GFS
and 00Z European on this track is why this seems to be the likely
track. The clipper will bring a period of moderate forcing for
ascent, likely generating a large swath of 1 to 2 inches of snow
across the Northland. Most of the snow will fall overnight, but
there will be a little lingering snow in northwest Wisconsin after
dawn. The 00Z Canadian and 00Z NAM12 have a track more to the north,
but still result in 1 to 2 inches of snow for the Northland.

The Northland will see its next blast of Arctic air in the wake of
the early Monday Clipper. Confident in widespread northerly wind
gusts of 20 to 30 mph Monday afternoon and evening, and the gusts
could be as high as 35 mph. There will be strong cold air advection
and pressure rises, and good and relatively deep mixing. The GFS and
NAM12 have 25 to 35 knots within the mixing layer. Snow flurries are
possible through Monday afternoon and evening. An additional 2
inches of snow is likely for areas along and near the Gogebic Range
in northern Wisconsin because of lingering lake effect snow Monday
afternoon through Monday night.

A weak area of high pressure will move through the Northland Tuesday
afternoon and evening, but then another, weaker, Clipper will dive
south and move through the Northern Plains and/or western Great
Lakes Wednesday night and Thursday. This clipper may only bring a
light coating to around 1 inch of snow. However, the GFS has a
stronger Clipper than the European and Canadian, and suggests the
potential for another 1 to 2 inches. This Clipper might also bring
another period of gusty winds with its northerly blast of Arctic
air, but less confident because of the various modeled tracks.

The GFS, European, and Canadian suggest another weak Clipper could
track from Manitoba through or near Ontario and/or the Minnesota
Arrowhead sometime late Friday through Saturday. This could bring a
light coating of snow to some areas of the Northland.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1219 PM CST Sat Dec 9 2017

MVFR stratus will linger this afternoon. Low-level moisture is
trapped beneath a temperature inversion aloft. A wedge of drier
air is found above the inversion, but is unable to mix into the
cloud layer. A few holes are possible, but think MVFR ceilings
will continue this afternoon. Scattered snow showers will continue
as well resulting in occasional visibility reductions between 2
and 5 miles. Winds aloft turn westerly by this evening moving a
drier airmass into the area. Look for the low stratus to become
scattered. Snow showers are expected to end with the departure of
the low clouds. Winds aloft turn northerly once again late tonight
pulling another surge of moisture into the region. Look for
ceilings to lower into MVFR range again tonight.


DLH  16  13  24  16 /  10  10   0  80
INL  14  10  20  10 /  10  10  10  80
BRD  21  17  28  22 /   0  10  10  60
HYR  16  11  26  15 /  10  10  10  70
ASX  18  14  25  15 /  40  20  20  80


WI...Winter Weather Advisory until 4 PM CST this afternoon for WIZ003-



LONG TERM...Grochocinski
AVIATION...Huyck is the U.S. government's official web portal to all federal, state and local government web resources and services.