123
FXUS63 KARX 051827
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
125 PM CDT Thu Jun 5 2025

.KEY MESSAGES...

- Periodic showers Friday through Monday with isolated thunder
chances here and there. Severe risk low to none. Forecast rainfall
amounts roughly 1/4 to 1". Cool to seasonable with highs Monday
trending in the 60s.

- Warmer and drier conditions for the middle part of the new week.
Highs looking to climb back into the 80s.

&&

.DISCUSSION...
Issued at 130 PM CDT Thu Jun 5 2025

* WEEKEND: periodic showers, some thunder chances, cooler.

Medium range guidance remain in good agreement with spinning bits of
shortwave energy across the region this weekend before dropping a
more defined trough/500 mb low southward out of Canada Sat
night/Sun. Accompanying sfc cold front will lead the trough across
the region Sun morning while a westward hanging trough/secondary
cold front could linger through Mon.

Saturation will be a challenge initially with RH fields and forecast
soundings pointing to mostly mid/upper level moisture for the
forcing to work on. Depth increases working into the weekend but
there isn`t much for low level moisture transport. Locally, the
shower chances creep up by Sat afternoon and will persist into
Monday. Likely more of the "on and off" variety. Not necessarily a
rainout for any outdoor activities, but something you might have to
"dodge" periodically.

For amounts, GEFS and EPS at odds with how much could/would be
realized. 25-75% in the EPS still sit from 1/4 to 3/4". The GEFS is
more enthusiastic in its latest run, roughly from 1/2 to 1 1/4". So
TBD with how amounts will trend for the weekend and will hold with
the WPC forecast.

Instability isn`t much either, but enough there from time to time to
spark a few storms. The better, stronger shear generally sits south
of the local area. Not expecting severe weather and probably only a
low end risk for a stronger storm or two.

With the clouds and showers, along with an influx of colder air as
the upper level trough moves in, temps look to hold at/below the
early June normals. Monday is looking like that coolest of the days
with models favoring 60s for highs.


* MOVING THROUGH NEXT WEEK: drier, warmer period still on tap for
  mid week. Next weekend could be more active with shower/storm
  chances.

The long range guidance continues in good agreement with building an
upper level ridge across the region, as early as Tuesday, persisting
into Friday. WPC clusters show this well, albeit with some
differences (but expected) in strength/positioning. A potential
trend of note is that the clusters are suggesting the ridge may not
be as stout as earlier runs suggested, nor stick around as long.
This would allow shortwave troughs to punch eastward and across the
upper mississippi river valley, with accompanying shower/storm
chances. Could also temper potential heat back a bit. Something to
watch.

As for temps, EPS and GEFS still favor a return to the 80s for
highs, with the EPS the warmer of the ensemble guidance: half of its
members above 80 from Wed into the weekend with a few encroaching on
90. Not "hot" by any means but warmer than this weekend - likely
above normal.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1125 AM CDT Thu Jun 5 2025

CIGS: increasing high/mid level clouds tonight, mostly 7-10kft
expected. CIGS likely to hold through the better part of Friday day,
with some scattering for the evening hours. More cigs are looking to
move in overnight Friday with some models hinting MVFR possible by
Sat morning (for a few hours).

WX/vsby: bits of shortwave energy could trigger scattered showers
across the region tonight through Friday. How widespread and where
is problematic given the somewhat "dirty" nature to the atmosphere -
no clear cut, well developed system. CAMS don`t produce much, but
could be suffering from a low QPF bias. Also, high bases to the
cloud deck and drier air sub cloud will work to evaporate what
falls. All said, feel some showers will be realized, but whether
those impact KRST/KLSE is uncertain. For now, will keep the forecast
clear of pcpn. Later updates/forecasts may need to add some
VCSH/SHRA based on radar/short term trends. Don`t anticipate any
vsby restrictions.

WINDS: light and somewhat variable through Friday.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.

&&

$$

DISCUSSION...Rieck
AVIATION.....Rieck