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Area forecast discussion
National Weather Service Duluth Minnesota
1217 am CDT Mon Oct 23 2017

Short term...(this evening through monday)
issued at 331 PM CDT sun Oct 22 2017

At 330 PM, skies were clear across all but the far southeast
portion of the County Warning Area. The rain showers that had moved through
northern Wisconsin earlier had moved off to the east. With full
sunshine today, temperatures topped out in the lower 60s across
portions of the western cwa, with temperatures limited to the
upper 40s to around 50 in Iron, price and Ashland counties. Winds
were gusty from the west to southwest, especially west.

The focus for tonight will be the area of low pressure moving in
from the west/northwest. This system was located in southern
Saskatchewan as of mid afternoon, and was rapidly moving across
the southern Canadian prairies. Rain showers had already developed
across portions of North Dakota. Winds will switch to the
southwest ahead of this system overnight, as clouds and rain
showers spread back in from the west/northwest.

Most of the showers will spread into the west/northwest portion of
the County Warning Area overnight, with a better chance of showers overtaking the
Northland on Monday. Have raised pops into the likely range across
a larger area of northern Minnesota on Monday, especially in the
area from the Iron Range northward. Rainfall amounts will
generally be under a quarter of an inch, although rain showers
could be fairly numerous by afternoon. Winds will switch to the
northwest from west to east as the low pulls off to the east, with
gusty winds into the 20 to 30 mph or higher at times. The cooler
air being pulled down behind the low will limit the high
temperature to 50 at International Falls, and around 60 south.

Long term...(monday night through sunday)
issued at 331 PM CDT sun Oct 22 2017

This week will be much cooler than last week, that's for sure! Highs
will mostly be in the 40s. A weak Canadian clipper could bring light
rain and snow, but our attention is focused on a much more potent
clipper later this week. This clipper over the latter half of the
week could bring the Northland it's first accumulating snowfall.

Canada's cold air spigot will be on Monday night and Tuesday. The
850 hpa temperatures will drop several degrees and dip to -4 to -6
degrees celsius. The cold air advection and cloud cover Monday night
will mean gusty winds overnight and continuing into Tuesday. Much
drier air will filter into the Northland Tuesday, so it should clear
out by the afternoon (except downwind of lake superior).

A surface ridge will quickly swing through the Northland late
Tuesday and Tuesday night. A weak Canadian clipper, though, will be
coming down into the Northland (from northern Saskatchewan and
central/southern manitoba) by late Tuesday night. This clipper could
bring light rain and snow late Tuesday night and Wednesday morning.
It looks like any snowfall accumulating would be very light, a
dusting or so.

Our primary focus is on a much stronger clipper late this week. The
GFS, European, and Canadian have been indicating an Alberta clipper
will track across southern Canada Wednesday and will likely move
into the northern plains and upper Midwest Wednesday night and
Thursday. The GFS and European are in fairly good agreement on this
scenario, and continue to show this clipper slowing down and winding
up over the upper Midwest and Great Lakes late Thursday through
early Saturday, before finally moving out of the region Saturday.
However, the latest Canadian leaves some question on the track
because it's clipper tracks much farther north and more
progressively than the GFS and European. The GFS and European
indicate this clipper will have some relatively deep moisture, and
at the least bring rain to the Northland. The GFS and European also
suggest there could be periods of accumulating snowfall over parts
of the Northland while the storm passes through the region, and
potentially lake enhanced and lingering lake effect snow downwind of
Lake Superior in northern Wisconsin. The Canadian track though will
barely brings any rain or snow to the Northland, maybe a dusting
across the Canadian border area. The gist is this could bring the
Northland it's first snow, or might not at all. It's too early to
speculate on snowfall amounts, but we will be providing more details
with subsequent forecasts.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1216 am CDT Mon Oct 23 2017

A trough will move over the Northland tonight, continue east
Monday and clear the area Monday night. Clouds have thickened this
evening and will continue to do so into Monday. There will be a
chance for showers tonight into Monday, highest over northern
areas. Ceilings will lower from VFR to MVFR Monday afternoon into
Monday evening for most areas as colder air moves in on northwest
flow. The wind will be southerly today then turn west then
northwest on Monday into Monday evening. Winds will increase in
strength Monday afternoon into the evening.

Low level wind shear will occur for a time but weaken and shift east
overnight.

&&

Preliminary point temps/pops...
dlh 43 55 35 43 / 30 40 30 10
inl 43 51 30 42 / 60 60 20 0
brd 45 54 35 45 / 50 50 10 0
hyr 40 58 36 45 / 20 40 50 30
asx 44 59 38 46 / 20 40 60 40

&&

Dlh watches/warnings/advisories...
WI...none.
Minnesota...none.
Ls...gale watch from late tonight through Tuesday afternoon for
lsz121-140>143-146>148.

Small Craft Advisory until 4 PM CDT this afternoon for lsz140-
141.

&&

$$

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