Area Forecast Discussion
Issued by NWS Duluth, MN

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FXUS63 KDLH 220950
AFDDLH

Area Forecast Discussion
National Weather Service Duluth MN
350 AM CST Mon Jan 22 2018

.SHORT TERM...(Today through Tuesday)
Issued at 313 AM CST Mon Jan 22 2018

The winter storm system that has been advertised for the last
several days arrives over northwest Wisconsin today, which will
lead to between 6 to 9 inches of new snowfall over our eastern
northwest Wisconsin counties.

For this morning, the main areas of snow will be over Price and
Sawyer counties and points north and west to the Twin Ports. We`ve
had some steady light snow at NWS Duluth for the last several
hours, thanks to a persistent northeast fetch off Lake Superior.
The models have been doing poorly in determining the
precipitation types as the soundings indicate more freezing
drizzle than light snow as there`s not much in the way of ice
production aloft. Moreover, there`s a fairly deep dry layer
between 900-600 mb, with a shallow saturated layer near the
surface, per the latest RAP/NAM model soundings. As the system
approaches, snow should be the dominate p-type, but freezing
drizzle will be possible, especially if ice loss occurs. This
difference in p-types will play a role in the amount of snow
accumulation and ice accretion over northwest Wisconsin. The
latest snowfall forecast for snow amounts will be between 3 to 9
inches southeast of an Ironwood, MI to Spooner, WI line, with the
heaviest snow falling over Price county. With the potential for
freezing drizzle, some higher ice accretion amounts will be
possible this afternoon and evening. Given how snow, instead of
freezing drizzle, is on-going, we are thinking that the ice
accretion amounts will be slightly lower than from the previous
forecast, but still could reach over 0.10" from Cable, WI
northeast towards Ashland and Kimball. The only change to the
Winter Storm Warnings/Winter Weather Advisories was to issue a
Winter Weather Advisory for Bayfield county, keeping all else the
same.

Once the system departs late this evening and overnight, some
light lake enhanced snow should linger over the Lake Superior
snowbelt region from the Bayfield Peninsula southeast towards the
Gogebic Range. Some of the synoptic snow might linger still over
Price county as well. However, amounts should be light, with only
a few tenths of an inch expected in these areas. Otherwise, skies
will decrease from the north as surface high pressure over Hudson
Bay noses into the region, with mid-level ridging to the west.
The best chances of clearing skies will be the north, which should
support some decent radiative cooling as winds decrease. Leaned
towards the colder guidance for overnight lows tonight, with
values ranging from near zero over the BWCAW area, to the low to
middle teens over central Minnesota and northwest Wisconsin.
Tuesday looks to be mostly sunny and dry across the Northland,
with highs in the upper teens to middle 20s. Clouds will be on the
increase from west to east in the afternoon ahead of a mid-level
wave that will translate across the region Tuesday night and
Wednesday morning.

.LONG TERM...(Tuesday night through Sunday)
Issued at 313 AM CST Mon Jan 22 2018

The extended period will feature a couple weak systems that will
bring mainly light chances for precipitation and a warming trend
peaking Friday.

A shortwave will move through the Northland late Tuesday night into
Wednesday evening accompanied by warm air advection. An area of high
pressure will precede this wave and move across northern Ontario.
The high will serve to veer low level winds from east to
southeast Tuesday night then to south to southwest Wednesday
evening. Colder 850MB temperatures, from -12C to -14C, will be
over far western Lake Superior and a chance for lake effect snow
will occur from late Tuesday evening into Wednesday along portions
of the North Shore. Light snow accumulation will be possible.
There will be a chance for light snow over portions of far
northern Minnesota from the shortwave as well with any
accumulation light. An upper level ridge will build over the
Northern Plains into Saskatchewan and Alberta Wednesday night with
increasing warm air advection downstream over the Northland. Dry
conditions are expected Wednesday night into Thursday night. The
upper ridge will continue east during this time passing east of
the area Thursday night. An area of low pressure will move into
the region late Thursday night into Friday passing east Friday
night. High temperatures Wednesday will be in the twenties then
warm into the mid thirties to mid forties on Friday. A chance for
light rain or light snow will occur Friday with mainly chances for
light snow Friday night into Saturday. Most of the forcing with
the low, which will track north of the region, will occur north of
the International Border, so rain/snow accumulation is expected
to be light Friday into Saturday.

High pressure will build over the region next weekend providing most
of the area with dry weather and cooling temperatures. The exception
to the dry weather will be in the snowbelt along Lake Superior`s
south shore which will have a chance for snow showers. High
temperatures are expected to cool into the teens to lower twenties
by Sunday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1140 PM CST Sun Jan 21 2018

Widespread IFR cigs expected until after sunrise. Cigs will then
vary with some improvement to MVFR at HIB and INL around 17Z, then
VFR by 21Z. DLH, BRD and HYR will stay in the IFR range through
much of the forecast, with some improvement to MVFR or VFR, at
BRD and DLH toward the end of the forecast. Look for HYR to remain
at IFR. The snow will be confined to HYR after 13Z. Gusty winds
are expected at DLH, BRD and HYR after sunrise.


&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  26   9  22  10 /  20  20   0  10
INL  24  -1  17   4 /  10   0   0  10
BRD  29  12  24  13 /  10  10  10  10
HYR  30  15  25   8 /  80  70   0  10
ASX  29  17  23   9 /  70  70  10  10

&&

.DLH WATCHES/WARNINGS/ADVISORIES...
WI...Winter Storm Warning until midnight CST tonight for WIZ003-004-
     008-009.

     Winter Weather Advisory until midnight CST tonight for WIZ001-
     002-006-007.

MN...None.
LS...None.
&&

$$

SHORT TERM...JTS
LONG TERM...Melde
AVIATION...GSF



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