Area Forecast Discussion
Issued by NWS La Crosse, WI

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FXUS63 KARX 271148

Area Forecast Discussion
National Weather Service La Crosse WI
648 AM CDT Tue Sep 27 2016

.SHORT TERM...(Today through Wednesday)
Issued at 241 AM CDT Tue Sep 27 2016

Main concern in the short term is rain chances with large upper
low spinning through the Great Lakes Region for the next few
days. Satellite imagery shows the low spinning over eastern
Lake Superior, and it will slowly drop south today. An extensive
shield of cloud cover is seen, and models all indicate overcast
conditions will prevail as the system advances southward. There is
enough instability and lift in this cold pool that widespread
light showers should occur. Bumped rain chances up as it appears
rain will occur, albeit amounts will be on the light side. With
the clouds and showers, temperatures will not go up too much.
Highs will only be in the 50s for most areas, except for over the
far southern counties where the sun will hang on longest.

.LONG TERM...(Wednesday Night through Monday)
Issued at 241 AM CDT Tue Sep 27 2016

Upper system finally shifts just far enough east by Wednesday
night that the main cloud shield and any rain threat will be out
of the area. This occurs as upper ridging tries to build in from
the west. But these two features will continue to battle all the
way into the weekend as the upper system closes off and settles
into the Ohio Valley to finish out the week. We may still see some
influence from this...with clouds perhaps spinning toward us from
the east or southeast. The big question comes in by the weekend as
the models try to figure out how to handle the closed system and
how it will react to the weakening ridge and deepening western
trough approaching from the west coast. ECMWF has for a couple of
runs now retrograded the low back west toward the area spreading a
chance for showers from east to west across WI/IL toward the
Mississippi River Valley by Saturday. For now we are favoring the
solutions that keep the rain and main impact from that just east
of the forecast area. But this bears watching. Either way,
attention will quickly shift to the advance of the western trough
moving in for the Monday/Tuesday timeframe next week. Temperatures
and instability will be on the increase, with a rainy period
again in the offing for the first half of next week.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 648 AM CDT Tue Sep 27 2016

Conditions will fall to MVFR today and possibly IFR tonight. Rain
showers will overspread the TAF sites today, mainly in the
afternoon, as low pressure moves in from the north. Mainly MVFR
conditions are expected with the arrival of the rain showers then
as the showers taper off this evening, IFR conditions are
possible. Ceilings may fall to around 800 ft tonight. These lower
ceilings should then improve as the low exits the region Wednesday
morning and drier air moves in.


Issued at 241 AM CDT Tue Sep 27 2016

Flood Warnings continue along the lower Kickapoo River, but the
river should drop below flood stage at Gays Mills and Steuben by
tonight. The Yellow River at Necedah will remain above flood stage
for another few days. Along the Mississippi River, water levels
are now falling at La Crosse, with the crest occurring now in the
Brownsville and Genoa areas. The crest is expected from Genoa down
through Guttenberg by Thursday, with minor flooding anticipated
through this region. With about a week of dry weather, hopefully
all rivers can get back down to a more reasonable level before the
rains hit again next week.




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