672
FXUS63 KARX 161054
AFDARX

Area Forecast Discussion
National Weather Service La Crosse WI
554 AM CDT Thu Oct 16 2025

.KEY MESSAGES...

- On and off showers into Saturday night. Rainfall amounts of up
  to an through Saturday night possible.

- Warmer than normal temperatures through the weekend with the
  warmest day being Friday where the highs will be in the 70s.

&&

.DISCUSSION...
Issued at 234 AM CDT Thu Oct 16 2025

Today through tonight

Latest water vapor satellite imagery shows upper level ridge over
central United States and a weak shortwave trough overtopping the
upper level ridge over northern Iowa/southern Minnesota. Per mosaic
radar...showers and a few storms were occurring over
northern/central Iowa in association with the shortwave trough.

The shortwave trough will lift northeast across the forecast area
today. Moisture transport/convergence and weak forcing will continue
to allow showers to overspread the forecast area. Preciptable water
values of 1 to 1.5 inches remain over the forecast area today. Given
the weak forcing QPF amounts may produce up to a third of an inch
rainfall across parts of the forecast area through this evening.
Latest 16.00z NAM indicate 200 j/kg of 0-6km most unstable CAPE
across the region. A few storms will be possible embedded in the
showers.

As shortwave trough moves northeast...warmer air aloft advects into
the area and 925mb temperatures warm to plus 10 to plus 18 degrees
celsius by 00z Friday. High temperatures are expected to rise into
the upper 50s across north central Wisconsin to the lower 70s across
parts of northeast Iowa/southeast Minnesota.

Friday into Saturday

Upper level ridge builds east and upper level closed low over the
Rocky Mountains lifts northeast into southern Ontario/Manitoba
Canada. Impulses embedded in the southerly flow aloft ahead of the
upper level closed low/trough will be the focused for ongoing on/off
showers mainly Friday afternoon into Saturday. The latest 16.00z
NAM/GFS shows narrow axis of up to 200 j/kg of 0-6km most unstable
CAPE. An isolated or a few storms will be possible Friday
afternoon/evening across parts of the forecast area. Much of the
moisture convergence and vertical motion moves east of the forecast
area Saturday. However...some lingering moisture and lift could
produce some showers across the far eastern areas of the forecast
area.

With the southerly flow aloft ahead of the upper level closed
low/trough...warmer air filters into the region Friday. 925mb
temperatures continue to warm and be plus 18 to plus 20 degrees
celsius by 00z Saturday. Temperatures will remain above normal for
both Friday into Saturday. With the warmest day Friday highs are
expected to climb into the middle to upper 70s with slightly cooler
highs Saturday in the middle 60s to lower 70s.

Sunday through Wednesday

Main forecast concerns Sunday through Wednesday are rain chances
through the forecast period. An active weather pattern continues
from late this weekend into middle of next week. The latest 16.00z
deterministic and ensemble models are in decent agreement through
late this weekend moving upper level trough/low east of the Great
Lakes/Midwest Region. Upper level ridge amplifying over the Northern
Plains/Upper Midwest will allow for diminishing precipitation
chances west to east across the forecast area Sunday. Brief period
of dry weather is expected Monday...as upper level ridge builds into
the Great Lakes/Upper Midwest Region Monday. Then...the
deterministic/ensembles diverge on the strength of the upper level
closed low/trough middle of next week. Some of the ensemble members
indicate upper level trough closes off over southern Ontario Canada
by 00z Wednesday. Pieces of energy rotating around upper level
trough/closed low will provide chances of rain across the forecast
area Tuesday into Wednesday. Temperatures Sunday into Wednesday will
remain near or slightly above normal with lows mainly in the middle
30s to lower 40s and highs in the middle 50s to middle 60s.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 549 AM CDT Thu Oct 16 2025

Poor aviation conditions at issuance with MVFR to LIFR stratus
and visibility reductions due to light rain and/or fog should
improve over the next 6-12 hours as ceilings lift from south to
north. There is a small (10%) chance for thunder around RST
early in the period, too low for a mention in the TAF. After 00z
Friday, low level jet develops and with some difference in
direction between this and the southerly winds at the surface,
low-level wind shear looks to develop overnight. Should expected
wind speeds at the surface increase, then this risk would fall
below the threshold for a mention but have included it in the
TAFs.

&&

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

&&

$$

DISCUSSION...DTJ
AVIATION...Ferguson