384
FXUS63 KARX 142325
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
625 PM CDT Mon Jul 14 2025

.KEY MESSAGES...

- Warmer and muggier today and Tuesday with highs in the mid-80s
  to near 90s.

- Next round of storms comes mainly on Wednesday. How storms
  evolve on Tuesday night will play a role in storm coverage and
  intensity Wednesday afternoon.

- Cooler temperatures for the end of the week with highs in the
  70s and low 80s for Thursday through the weekend.

&&

.DISCUSSION...
Issued at 115 PM CDT Mon Jul 14 2025

Today through Tuesday Evening: Warm and Dry Muggy

Summertime air returns on southerly flow with highs reaching
into the mid-80s to near 90 today and Tuesday. Cannot fully rule
out some afternoon convection along a retreating boundary north
of I-90 this afternoon before the cap builds in, but details
are too muddy to hang one`s hat on and left PoPs at 10% or less.


Tuesday Night - Wednesday: Severe Storm Potential?

Main area of interest in the forecast is the Tuesday night into
Wednesday evening timeframe. A quasi-stationary boundary
situated over central MN will be the focus for a line of
convection that initiates in the late afternoon and evening
hours on Tuesday. The longer range of the 14.12Z HREF members
are struggling to bring this line of storms as far south a
previously progged given the nearly line-parallel upper level
WSW flow. This results in less convective debris during the
morning and a cleaner environment ahead of a rather nebulous
surface low that lifts out of the Mid-Missouri River valley
Wednesday morning and across our area for the afternoon.

The medium range global models are depicting a broad and weak
cyclonic flow with the potential for the low centroid to wander
or even retrograde along the surface baroclinic zone. Combined
with uncertainties regarding the thermodynamic environment
cleanliness, this makes for a challenging assessment of the
severe weather potential. The deeper shear is not too
impressive, the question boils down to whether we will see low-
level mesocyclones with any convection that does develop. The
weaker flow and presence of a wind shift along the front could
present a window of opportunity for landspout processes under
any stronger updraft--possibly amplified by any low-level mesos
that manage to form.

It is no surprise then that there is a modest spread in the
temperature forecast for Wednesday, dictated by the degree of
cloud cover and showers. The front looks to clear the forecast
area by the evening as the surface low finally tracks to the
east, bringing the precipitation with it.


Late Week: Cooler, Drier End, Warmer and Wetter for the Weekend

The end of the work week will be characterized by a period of
cooler weather more typical of mid-September as a shot of polar
air grazes the region. The chances of precipitation during this
window are fairly low (< 20%) and would be towards the Highway
18 corridor and on south. Overnight lows will be driven by the
degree of cloud cover and could fall into the mid to upper 40s
(the NBM 10th percentile) Thursday night in favored spots east
of the Mississippi if conditions align perfectly. By the
weekend, the progressive zonal flow undulates again and warm air
advection ensues. This will herald the arrival of more risks
for storms during the weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 624 PM CDT Mon Jul 14 2025

The Wisconsin River and its tributaries will likely see some
valley fog overnight. Otherwise, VFR conditions are expected.
South and southwest winds will be in the 10-15 knot range.

&&

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

&&

$$

DISCUSSION...Skow
AVIATION...Boyne