581
FXUS63 KARX 032159
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
500 PM CDT Thu Apr 3 2025

.KEY MESSAGES...

- A drier forecast on the docket for the upcoming week with a
  passing glance of rain showers Friday night and light snow on
  Monday.

- Seasonably cool temperatures for the rest of the week and into
  early next week with highs generally in the 40s to low 50s.
  Coldest day of the week is looking to be Monday with highs
  stuck in the 30s.

&&

.DISCUSSION...
Issued at 210 PM CDT Thu Apr 3 2025

Temperature Outlook through Early Next Week

Predominately cyclonic lower to mid tropospheric flow lingers
into early next week, keeping temperatures at or below seasonal
normals (lower 50s for highs). As longwave troughing breaks
down across the western CONUS at the end of the weekend, the
northern stream jet ushers in a cold front Sunday night, setting
the stage for a rather raw Monday with highs in the 30s and
lows Monday night falling into the teens and 20s. The pattern
begins to moderate by Tuesday and by Thursday and beyond we
could be looking at a period of warmer than average
temperatures.

Confidence in the temperature forecast for the next 5-7 days is
fairly high given the tight clustering of the GEFS/EPS ensemble
guidance. Temperatures for the next few days will hinge on
whether we see any clearing in the clouds, which would serve to
increase the diurnal spread. There are still some small
differences in the timing of the front for Sunday, which will
play into how when temperatures decrease--though the magnitude
of the decrease is nearly the same amongst all the guidance.

Low Risk for Rain Friday Night

The region will find itself between the southern and northern
stream systems for Friday, with the main slug of Gulf moisture
pegged to stay south of the area and the approaching Dakota cold
front decaying as it moves through Minnesota. The initial runs
of the convective allowing models have come in drier for Friday
and have likewise trended the forecast in this direction.
Indeed, if the recent runs of the HRRR/RAP come to fruition, we
may see little to no rain for Friday night.

Quick Round of Snow Monday

Modest frontogenesis along the cold frontal surface Sunday
night into Monday morning looks to bring a line of scattered
snow showers to the region, mainly east of the Mississippi
River. Initial deterministic forecast soundings show these
showers mainly tied to the front and clearing quickly--the
broader PoPs reflect the differences in the timing of the front.
The ensemble members diverge in how they handle any systems
moving through midweek next week, resulting broad- brushed PoPs
that will be reigned over the coming days.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 500 PM CDT Thu Apr 3 2025

CIGS: low saturation has been hard pressed to clear this afternoon,
despite the approach of a weak sfc high and slight ridging a loft.
RAP/HRRR adamant that the low level moisture isn`t going anywhere
overnight either...and likely sticks around through Friday night.
The result is more MVFR to low VFR for cigs.

That said, there has been erosion on all sides of the current cloud
mass over the TAF sites (along I-90) thanks to daytime mixing. This
will likely slow up/halt with loss of heating, and could get re-
expansion. Will keep an eye on satellite trends and adjust if needed.

WX/vsby: weak instability tonight via the RAP/HRRR soundings, but
don`t think there is enough lift/deep saturation to support any
pcpn. Will leave dry.

WINDS: north becoming light east/vrb later tonight...turning southeast
for Fri bu holding under 10 kts.

&&

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

&&

$$

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