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000 
FXUS63 KDLH 181140 AAA
AFDDLH

Area Forecast Discussion...UPDATED
National Weather Service Duluth MN
540 AM CST Mon Nov 18 2019

.UPDATE...
Issued at 540 AM CST Mon Nov 18 2019

Updated below for 12z Aviation Discussion.

&&

.SHORT TERM...(Today through Tuesday)
Issued at 345 AM CST Mon Nov 18 2019

Forecast focus will be on precipitation type and amounts tonight 
into Tuesday.

Weak ridging was moving through the Northland this morning leading 
to dry conditions but the ridge isn't strong enough to scour out the 
clouds. We expect clouds to stick around through much of the day 
today. The lower clouds may diminish in spots but there will be more 
clouds moving in ahead of a warm front and shortwave. Most of 
Northland will remain dry today with highs climbing into the lower 
to middle thirties. There will be a chance precipitation over the 
western half of the area late this afternoon, mainly along and 
west of a Hinckley to Hibbing to International Falls line. The
precipitation will then spread east tonight. Precipitation type 
when most of the QPF will fall will be determined by boundary 
layer temperatures. A mix of light rain or snow will start out 
this afternoon then will transition to mostly light snow as it 
spreads east overnight. Model consensus is that the area of 
precipitation will diminish in coverage/intensity late tonight and
we have just chance POPs over the Arrowhead. Light freezing 
drizzle will be possible later tonight into Tuesday morning as the
forcing weakens and we lose ice aloft. However, confidence in how
much precipitation will occur behind the main area is low and we 
don't anticipate the need for a Winter Weather Advisory at this 
time. Snowfall amounts will range from a few tenths of an inch to 
around an inch and a half, with most of it falling tonight. The 
higher amounts will be most likely along and north of a Walker to 
Grand Rapids to Hibbing line. The precipitation will end/diminish 
from south to north late tonight into Tuesday. Highs Tuesday will 
range from the lower to mid thirties far north to 35 to 40 from 
the Brainerd Lakes into northwest Wisconsin.

.LONG TERM...(Tuesday night through Sunday)
Issued at 345 AM CST Mon Nov 18 2019

A weak shortwave will clear the area Tuesday night into Wednesday 
morning as ridging aloft and surface high pressure move overhead. 
This will push to the east heading into Wednesday afternoon and the 
focus then shifts to the larger system for the Wednesday night into 
Thursday timeframe. The first round of snow will be in association 
with a shortwave moving from the Northern Plains into the Upper 
Midwest Wednesday afternoon. Light snow showers will spread across 
the Northland through the afternoon and into the evening hours. At 
the same time, another wave will emerge from the southern Rockies 
and lead to the development of a low somewhere in the 
Kansas/Colorado/Oklahoma border region. The 18.00 suite is in fairly 
good agreement in tracking this low to the Omaha area Wednesday 
night and then into southern Wisconsin by midday Thursday before 
moving into eastern Ontario Thursday night. With this track a touch 
further to the west than last night's runs, this will bring a bit 
more in the way of snow to the Northland Wednesday night into 
Thursday morning. Areas along and east of the Iron Range into 
northwest Wisconsin stand the best chance of being impacted by this 
system. A few inches of snow looks probable at this point with the 
highest amounts in north-central Wisconsin. There remain some 
questions in p-type at the onset of the main system arrival and 
subtle timing differences, but there is the potential for low-end 
advisory level snowfall in parts of northwest Wisconsin with the 
current forecast. 

Snow will quickly end Thursday evening as strong high pressure 
builds in from the Plains. However, some lake-effect snows may 
linger in northwest Wisconsin into Friday with dry conditions 
elsewhere. Models then diverge heading into the weekend with some 
models remaining dry while others bring a shortwave through that 
could lead to some snow, but chances are fairly low for this at this 
time. 

Temperatures will trend near to slightly below normal on Wednesday 
before cooling below normal for Thursday into Friday. Temperatures 
then moderate back to near to slightly below normal levels for the 
weekend.

&&

.AVIATION...(For the 12Z TAFS through 12Z Tuesday morning)
Issued at 540 AM CST Mon Nov 18 2019

A mix of MVFR and IFR ceilings will be seen this morning with IFR
sites expected to improve to MVFR by mid-morning. A warm front
will approach from the west this afternoon and bring rain/snow to
the terminals for the evening and overnight hours. This will lead
to IFR/LIFR ceilings and MVFR/IFR visibilities. These IFR or worse
conditions are then expected to persist through the end of the TAF
period and perhaps beyond before improving. Winds will be light
through the period at around 5 knots or less.

&&

.MARINE...
Issued at 345 AM CST Mon Nov 18 2019

No hazardous marine conditions are expected over the next 48 hours. 
Winds today and tonight will be south-southwest at 5 to 10 knots and 
then turn west-southwest for Tuesday and Tuesday night at 5 to 15 
knots. Waves will be 1 foot or less.

&&

.PRELIMINARY POINT TEMPS/POPS...
DLH  34  29  36  27 /  20  70  20  10 
INL  35  29  36  26 /  30  60  50  10 
BRD  38  32  39  27 /  50  70  10  10 
HYR  36  28  38  26 /  10  70  20  10 
ASX  36  27  38  28 /   0  50  40   0 

&&

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

$$

UPDATE...BJH

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