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Area forecast discussion
National Weather Service La Crosse WI
231 PM CDT Thu may 25 2017

Short term...(tonight through Friday night)
issued at 231 PM CDT Thu may 25 2017

Ridge of high pressure over the area providing a spectacular day for
the area with mostly sunny skies and temperatures this afternoon in
the middle to upper 60s.

For tonight...will be watching a mid-level trough and some 850-700mb
moisture transport and isentropic lift pushing into the area. This
will generate some higher-based altocumulus with perhaps a few
showers from time to time. Plan on lows dropping into the lower and
middle 50s.

Quasi-southwesterly flow aloft brings in another trough/weak surface
cold front through on Friday for shower chances. Could also see an
isolated thunderstorm or two in the afternoon as the NAM/GFS bring
in a weakening corridor of cape ahead of the trough/front in daytime
heating/moisture transport. Appears 0-3km MUCAPE peaks in the 500-
1500j/kg range across eastern Minnesota/northwest WI, waning as it moves
into WI. Otherwise, look for highs in the upper 60s to lower 70s
with partial sunshine.

Any lingering showers associated with the mid-level trough look to
exit east of the area by late in the evening with partly cloudy
skies the rule through the rest of the night. Overnight lows will
cool into the Lower/Middle 50s.

Long term...(saturday through thursday)
issued at 231 PM CDT Thu may 25 2017

Saturday will see a small-end chance of showers/isolated
thunderstorms mainly south of I-94 as another weak mid-level trough
and surface cold front push through. NAM brings in 0-3km MUCAPE of
500-1800j/kg Saturday afternoon ahead of the trough/front but bulk
shear looks rather weak, so severe threat looks minimal at this

For Sunday into Memorial Day...a deepening mid-level trough drops
into the region from Canada with increasing cooler/cyclonic flow
aloft. Steepening lapse rates will likely generate scattered showers
along with isolated afternoon thunderstorms. Look fro highs Sunday
in the upper 60s to the lower 70s, cooling into the 60s on Memorial

On/off shower chances continue through Thursday with lingering
cyclonic flow aloft. Otherwise, highs will remain below normal with
reading topping off mainly in the 60s.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1227 PM CDT Thu may 25 2017

Main taf concerns is the possibility of MVFR ceiling conditions late
in the taf period. Weak surface ridge will build into Wisconsin this
afternoon and allow for VFR conditions to prevail at both rst/lse
taf sites. A weak surface front is expected to move into western
Wisconsin by 18z Friday. The 25.12z GFS/NAM show weak lift and
moisture convergence in association with the surface front. The
combination of weak lift/moisture convergence...may produce isolated
showers across the area after 00z Friday. At this time will leave
shower mention out of both tafs. VFR conditions will continue to ceiling heights are expected to be above 10000 feet
through 15z Friday. After 15z... ceilings will lower into the MVFR
conditions. Will introduce MVFR conditions after 14z Friday at both
rst/lse taf sites.


Hydrology...231 PM CDT Thu may 25 2017

Runoff from heavy rainfall this past week will continue to cause
minor flooding along portions of the Mississippi River into next
week and also the Trempealeau River at Dodge through Friday. Be sure
to monitor river levels closely if you have any plans or interests
along these rivers. You can access this information on our website
at weather.Gov/arx.


Arx watches/warnings/advisories...


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