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Area forecast discussion
National Weather Service La Crosse WI
534 am CST sun Dec 8 2019

Short term...(today and tonight)
issued at 243 am CST sun Dec 8 2019

Another mild day today with stratus oozing in behind the boundary
as the cold air slides in.

Main attention in the short term is on precip event starting

As low level saturation deepens and weak lift develops in advance
of the main wave, expect drizzle to develop across the area
tonight. Where surface temperatures are below freezing (broadly
along and north of I-90), could see some drizzle freezing on
untreated surfaces. Although ice amounts are expected to be only a
few hundredths, the freezing drizzle could make for a bit of a
messy commute Monday morning in some spots.

Freezing drizzle/drizzle will continue until the main wave
approaches and full saturation occurs during the morning Monday.
Given the strength of the cold air, expect a quick transition
once the cold air surges south Monday morning, so made some
adjustments to accelerate the timing of the changeover slightly
from the model blends.

As for snow amounts, expecting a dusting to around 3 inches, with
the higher amounts north of I-90. If the changeover happens
faster or the wave tracks slightly farther south than currently
progged, amounts would nudge upward.

With gusty winds increasing Monday afternoon, especially west of
the Mississippi River, will need to keep an eye out for blowing
snow potential Monday afternoon into evening.

Long term...(tuesday through saturday)
issued at 243 am CST sun Dec 8 2019

Focus the rest of the week will be on plummeting temperatures
Tuesday through Thursday. Forecast is on track, so no notable
changes to the forecast in these later time periods this morning.
Still looking at the coldest air of the season so far with single
digit highs, sub- zero lows, and wind chills as cold as 25 below
by Wednesday morning.


Aviation...(for the 12z tafs through 12z Monday morning)
issued at 534 am CST sun Dec 8 2019

VFR conditions to start the day will be replaced by quickly
developing IFR ceilings and visibility into late afternoon and
this evening, as stratus clouds fill in behind the passage of a
cold front. Those clouds will thicken and lower into tonight,
helping develop areas of drizzle and freezing drizzle, depending
on surface temperatures. At the moment, lse looks just warm enough
for mainly drizzle (will watch closely), while rst increasingly
looks to receive a period of freezing drizzle toward or after 08z.
Ceilings and visibility in any drizzle should continue to further
decrease, likely reaching LIFR to even vlifr levels late tonight,
as surface winds of 5-10 knots from the south to start the day
shift northwest this afternoon and then northeasterly tonight.

Looking ahead after 12z Monday, any drizzle will change to light
snow before tapering off into the afternoon. 1 to 2 inches of snow
are currently forecast for both lse and rst.


Arx watches/warnings/advisories...

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