678
FXUS63 KARX 021130
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
530 AM CST Sun Nov 2 2025

.KEY MESSAGES...

- Breezy late this morning through early evening with southerly
  winds of 15 to 25 mph. Wind gusts of 30-40 mph possible,
  primarily west of the Mississippi River in unsheltered areas.

- Temperatures gradually warming up over the couple of days with
  highs reaching into the 50s and lower 60s on Monday and
  Tuesday.

- Shower chances (10-40%) tonight and into early Monday morning,
  primarily north of I-90 in west/north-central Wisconsin.

&&

.DISCUSSION...
Issued at 230 AM CST Sun Nov 2 2025

Today - Tonight: Fog This Morning then Turning Breezy, Shower
Chances Overnight

GOES-19 water vapor imagery and 02.06z RAP 500mb heights depict the
local area being subjected to some shortwave ridging which in turn
has provided some subsidence to clear our skies out overnight. As a
result, noting some areas of dense fog that have developed
across portions of southwest WI and northeast IA in combination
with light surface winds. However, this fog will likely be
short-lived this morning as winds will quickly increase with a
tightening surface pressure gradient for the day today with an
area of surface low pressure passing well to the north of the
region. This will result in 900mb winds increasing to around
35-40 kts by late morning which in tandem with mixing heights
into this layer should allow for some stronger gusts to be
translated to the surface. Consequently, the 02.00z HREF has
very high probabilities (70-100%) across much of the area for
wind gusts reaching 30 mph with some probabilities (30-70%) for
gusts over 40 mph in southeast MN. Therefore, if you have any
remaining halloween decorations outside, you may want to secure
them or bring them inside. Winds will gradually diminish after
sunset as diurnal mixing processes wane.

As we head into the overnight, an area of strong 600-700mb
frontogenesis will quickly swing through the area providing fairly
strong forcing aloft for showers to develop in this layer. The
trouble that many of the CAMs have picked up on is a fairly dry sub-
cloud layer underneath this as shown in the RAP/HRRR soundings
across the local area. However, saturation in the low-levels is
marginally more favorable as you head east of the Mississippi River
so this would be slightly more conducive to shower activity.
Consequently, have keep the "higher" precipitation chance (15-40%)
mention east of the Mississippi River, in accordance with the
measurable rainfall probability footprint of the 02.00z HREF.
Regardless, any showers we do see likely would only result in a
couple hundreths of an inch of precipitation at best.

Monday - Wednesday: Trending Warmer, Minimal Precipitation Chances

The forecast trends fairly quiet for the first half of the week as
zonal upper-level flow dominates the synoptic flow regime over the
local area. Consequently, the absence of northwesterly flow will
allow temperatures to increase slightly above normal beginning
Monday and Tuesday with the national blend keep highs generally in
the 50s with some spots topping 60 on Tuesday. Overall precipitation
chances remain fairly sparse with the only real shot for any
rainfall being on Tuesday night and into Wednesday morning as a
shortwave trough with an accompanying weak area of surface low
pressure push north of the area. As a result, the grand ensemble
(GEFS/EC/Canadian ensemble) has some low-end measurable
precipitation probabilities (10-30%) north of I-90. However,
given the relatively stronger forcing remains north of the area
in the current state of ensemble/deterministic guidance,
confidence is low for any precipitation during this period.

Thursday - Friday: Precipitation Chances Return, Staying Slightly
Warmer Than Normal

As we head into the latter half of the work week, the upper-level
pattern changes slightly as the quasi-zonal pattern ejects an upper-
level trough from the Rockies towards the Upper Midwest. While
deterministic guidance is still hazy on how this pattern behaves as
it pushes east towards the area, ensemble guidance generally agrees
on increasing precipitation chances into the Thursday night and
Friday timeframe as the grand ensemble (GEFS/EC/Canadian ensemble)
high probabilities (50-80%) for measurable precipitation east of the
Mississippi River. As far as temperatures are concerned, with mostly
zonal flow still in place until after the trough has completely left
the area, expecting temperatures to remain steady-state into
Friday. High temperatures will generally run a few degrees
above normal as the NBM keeps median high temperatures in the
upper 40s to 50s for Thursday and Friday. However, this needs to
be understood that depending on when the aforementioned trough
pushes east, northwest flow will establish itself across the
area bringing cooler temperatures, but this currently is more
favored to begin into the weekend at this time.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 530 AM CST Sun Nov 2 2025

Ongoing early morning LIFR fog in northeast Iowa and southwest
Wisconsin is battling the arrival of high clouds, thus wide
fluctuations in ceilings/visibilities are expected before the
fog clears by mid-morning. SSW winds increase to 10-20G20-30
kts for the afternoon, strongest west of the Mississippi River.
The winds lessen after sunset with short-lived periods of LLWS
possible overnight. A line of VFR showers moves south through
the area between 00-08Z, mainly impacting areas along and east
of the Mississippi River. Winds switch to the west behind these
showers. Minimal aviation impacts are expected afterwards
through at least midweek.

&&

.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Dense Fog Advisory until 8 AM CST this morning for WIZ061.
MN...None.
IA...Dense Fog Advisory until 8 AM CST this morning for IAZ018-019-
     029-030.

&&

$$

DISCUSSION...Naylor
AVIATION...Skow