Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 201707

Area Forecast Discussion
National Weather Service La Crosse WI
1207 PM CDT Fri Apr 20 2018

.SHORT TERM...(Today through Sunday)
Issued at 237 AM CDT Fri Apr 20 2018

A quiet weekend looks to be in store for the area. An area of high
pressure centered along the Iowa/Minnesota border this morning
will slide east and become centered over the Great Lakes tonight.
As it does this, it will become oriented by east/west which will
allow the ridge axis to extend back over the area through the
weekend. This will be enough to provide dry weather, but a system
passing by tonight and Saturday will bring some clouds to the
region. Water vapor satellite shows a cut off over the southern
Rockies this morning. This low will move east/southeast into the
lower Mississippi River Valley through Sunday. Short wave troughs
coming out of this system will attempt to top the ridge that will
be in place ahead of the low. As they near the top of the ridge,
they will start to weaken quickly as the flow increases and
becomes a convergent northwest flow into the long wave trough
along the East Coast. So while these waves will not bring any
precipitation to the area, they will produce plenty of clouds with
partly to mostly cloudy skies expected tonight into Saturday
night. Temperatures will be slowly warming through the weekend and
should be close to normal by Sunday with highs mainly in the 50s
with some spots topping 60.

.LONG TERM...(Sunday night through Thursday)
Issued at 237 AM CDT Fri Apr 20 2018

The next chance for any precipitation will come Tuesday. A short
wave trough is expected to move onto the Pacific Northwest Coast
Sunday and then work east across the northern Rockies. By Monday
night it will start to take on a more southeast movement that will
bring it across the region late Tuesday through Wednesday. This
system looks to come through with a positive tilt with the GFS
being stronger with it than the ECMWF. There should be enough
forcing from this system to produce some rain with differences
between the models on the timing and how much will occur. With the
GFS being stronger, it moves the rain in faster and has more over
the area than the ECMWF which takes the bulk of the rain south of
the region. With these differences between the models, plan to
keep the rain chances in the 20 to 40 percent range for now. Not
planning to introduce any thunder for Tuesday afternoon as both
the GFS and ECMWF only have around 250 J/Kg of MUCape.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 1207 PM CDT Fri Apr 20 2018

VFR conditions expected this afternoon through Saturday afternoon.

Increasing VFR cloud cover expected tonight into Saturday as an
upper low moves into the Central Plains. Broken-overcast cloud
bases will generally be at or above 9kft, with scattered-broken
cloud bases as low as 4-5kt at times late tonight into Saturday
morning. Otherwise, look for light and variable winds 5kt or less
tonight, becoming light south/southeasterly 5kt or less through
Saturday afternoon.


Issued at 237 AM CDT Fri Apr 20 2018

A flood warning remains in effect for the Trempealeau River at
Dodge with minor flooding is expected over the weekend. See the
latest flood statement for more information. As the recent snow
melts and runs off into area streams, additional flooding will be
possible, especially along the Kickapoo River with additional
details in the latest hydrologic statement.

A lot of the snow is expected to melt over the upcoming days with
daytime highs in the 40s and 50s through Saturday with some 60s
possible Sunday. Most of the area should drop back below freezing
at night to slow the melt at night. This melting snow will lead to
rises at noted above with additional rises possible into next week
as well.




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