Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 021008
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
408 AM CST Fri Dec 2 2016

.SHORT TERM...(Today through Saturday)
Issued at 407 AM CST Fri Dec 2 2016

The Northland remained between low pressure well off to the east and
weak high pressure over the Northern Plains. Plenty of low level
moisture remained under the inversion and will lead to mostly cloudy
skies today. There is a chance for a peak or two at the sun in
spots, but the majority of the region will remain mostly cloudy.
It`s possible some flurries or light freezing drizzle could fall
occur, but observations have not reported any precipitation so far
other than over portions of northwest Wisconsin. There has been some
lake effect precipitation in the snow belt and KPBH briefly reported
some light precipitation. We will continue a chance for snow showers
or patchy freezing drizzle over portions of the snow belt, but we do
not expect much accumulation. A spotter in Gile at 105 am reported
only 0.6 inches of snow since 1030 am Thursday bringing the total to
2.4 inches. The visibility at KIWD and webcams suggest little
additional snow has fallen since that report. Low level flow is
forecast to back through the day and become more westerly by this
evening. Expect highs today from the mid twenties to lower thirties.

Weak ridging will move into the Northland tonight and we expect the
clouds to stick around through the night. There could again be some
light freezing drizzle or flurries in spots tonight but coverage
looks to be too limited to include at this time. Lows tonight will
range from 20 to 25...but there could be colder pockets should any
brief clearing occur.

The ridge will continue east on Saturday into Wisconsin. It should
remain mostly cloudy although there is a better chance for a few
peaks at the sun.  Highs will range from the mid twenties to around
thirty.

.LONG TERM...(Saturday night through Thursday)
Issued at 407 AM CST Fri Dec 2 2016

Main concerns during the long term remain precipitation chances and
types with a late weekend system, the potential for several rounds
of precipitation Monday through Thursday, and cooler temperatures.

Not much change to the going forecast this morning due to continued
low confidence in sensible weather details. A trough of low pressure
and area of surface low pressure will move across the Dakotas
Saturday night and Sunday. Southwesterly flow ahead of the trough
will advect a combination of Gulf and Pacific moisture into the
Northland. The long trajectories and precipitation forecast to occur
south of the area will limit the precip potential locally.
Maintained a chance of rain and snow showers Saturday night through
Sunday evening, with precip spreading from west to east with time.
Unseasonably mild conditions across the Plains and Upper Midwest,
and the lack of a robust reservoir of cold air to tap, continues to
play merry hob with max and min temps and resultant precip types.
Seems cold enough for all snow Saturday night with a potential for
rain advancing up the I-35 corridor during the day. By mid-
afternoon, the possibility of a rain/snow mix will span from the
Brainerd Lakes along and south of MN Highway 210 to the Twin Ports
and then across most of northwest Wisconsin. Precipitation amounts
with this disturbance appear fairly low, generally less than 0.15
inches. There should be a heat and moisture contribution from
western Lake Superior, which would enhance snow/rainfall amounts
along the North Shore due to southerly winds ahead of the low. Snow
totals less than 2 inches are expected with this system. There is
also a potential for freezing drizzle Saturday night, however this
seems unlikely as of this morning and have kept precip types simple.

A weak ridge of high pressure will slide east across the area Sunday
night and Monday morning bringing a brief reprieve from
precipitation. Another stout thermal inversion is likely with this
weak ridge, which would keep skies mainly cloudy with isolated snow
showers or pockets of freezing drizzle possible.

The next potential troublemaker is forecast to move into the
Northern Plains and Upper Midwest Monday afternoon and Monday night.
Deterministic models and GEFS members are clustered around a similar
track with the surface and low-level trough. Kinematic details
expose more variety in potential outcomes with the GFS faster and
stronger and the CMC slower and farther south. ECMWF is in the
middle of the pack by Monday evening. The GFS solution would bring a
quick-hitting burst of rain and snow showers to the Northland Monday
afternoon through Tuesday afternoon while the ECMWF focuses the
heaviest precipitation over the eastern Dakotas into Manitoba. The
CMC solution would yield the most precipitation for our area with
precip along the warm front Monday night, and wrap around
precipitation hitting my northwest zones Tuesday afternoon and
evening. Given the differences in the details, maintained a
consensus approach for now.

Beyond Tuesday night the differences in deterministic guidance and
ensemble members increase markedly. ECMWF winds up a strong system
and lifts it from the southern Mississippi Valley into the eastern
Great Lakes through Thursday night, with marginal precipitation over
the Northland from a cutoff low over the Canadian Prairies. GFS has
a similar solution but is faster with the evolution and movement of
the surface low and associated shortwave trough. GEFS members are
spread out from southern Manitoba to the eastern Great Lakes. All of
the solutions this morning would yield some precipitation for the
Northland between Wednesday night and Friday. There is still a
possibility the system could actually track farther west than this
morning`s guidance suggests. Should a more westerly track emerge,
precip amounts and intensity would be much higher. For now, am
content to maintain a consensus blend until model consistency
improves.

Temperatures will start the period slightly above normal and will
gradually cool through Friday to near to slightly below normal. The
most notable changes in the temperatures will be in the daytime
highs with readings 8 to 12 degrees below normal by Friday.
Overnight lows will remain near to slightly above normal through
the period.

&&

.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1152 PM CST Thu Dec 1 2016

Widespread MVFR ceilings and VFR visibilities as of issuance time is
expected to continue through the TAF period. Some snow showers with
MVFR visibilities possible, but their timing is uncertain and
have gone with just VCSH with lower ceilings for now.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  30  24  29  24 /  10  10  10  30
INL  28  21  28  23 /  10  10  10  30
BRD  30  22  30  27 /  10  10  10  30
HYR  31  24  30  24 /  10  10  10  30
ASX  33  26  32  25 /  10  10  10  20

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
LS...None.
&&

$$

SHORT TERM...Melde
LONG TERM...Huyck
AVIATION...LE


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