Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 122046

Area Forecast Discussion
National Weather Service La Crosse WI
246 PM CST Sun Nov 12 2017

.SHORT TERM...(This evening through Monday)
Issued at 246 PM CST Sun Nov 12 2017

At 2 PM, IFR ceilings persisted across southwest Wisconsin and
parts of northeast Iowa. These clouds were associated with low
level moisture trapped below a subsidence inversion. The 12.12z
models are in agreement that these clouds will gradually move
southeast out of the area by sunset. Elsewhere skies were sunny to
partly sunny. Temperatures were in the mid 30s in north-central
Wisconsin. This was due to 1 to 3 inches of snow being on the
ground. Elsewhere temperatures ranged from the upper 30s to mid

For tonight, the models are in agreement that the low clouds
currently located over northwest Wisconsin and northern Minnesota
will move southeast into western Wisconsin. Meanwhile, the skies
in southeast Minnesota and northeast Iowa will range from mostly
clear to partly cloudy. With the clouds in the eastern sky, this
may hamper the viewing of the conjunction of Venus and Jupiter
early Monday morning. Low temperatures will be in the teens in
central and north-central Wisconsin and in the lower and mid-20s
across the remainder of the Upper Mississippi River Valley.

On Monday, the clouds will gradually increase as a short wave
trough approaches the region from the Northern Plains. The
combination of warm air advection and southerly winds will allow
temperatures to warm to near-normal levels (from the upper 30s to

.LONG TERM...(Monday night through Sunday)
Issued at 246 PM CST Sun Nov 12 2017

From Monday night into Tuesday, the 290K isentropic lift will gradually
increase west of the Mississippi River during the evening and
across the entire area Tuesday morning. This will gradually
moisten the low levels of the atmosphere. While the models are in
agreement that this will occur, they do differ on how fast this
will occur. This makes a difference on how fast the light
precipitation will develop across the area. The threat of freezing
drizzle is highly dependent upon on how fast this will occur. At
this time, it looks like temperatures will warm fast enough that
this threat look minimal. However, we will have to watch this

From Friday into Saturday morning, the models are in agreement
that cyclogenesis will taking place somewhere the Central Plains
into the western Great Lakes. In addition to questions on the
location of where this will occur, there are also questions on how
fast cold air will move into the region. Due to this, there is
much uncertainty on the precipitation types and temperatures with
this system.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1129 AM CST Sun Nov 12 2017

Next 24 hours will be tricky as high pressure settles over the
area. Current satellite/surface observations showing MVFR/IFR
stratus in fairly close proximity of the KRST/KLSE TAF sites
(within a county away). As high pressure settles overhead tonight,
low level moisture under the inversion could lead to areas of fog
and re-development of IFR stratus. The question is how widespread
the fog/stratus will be. Will introduce it in the 18z TAFs as
being right on the cusp but will have to keep a close eye on it
this evening as conditions set up.




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