Ossian, Iowa Weather Forecast Discussion

582
FXUS63 KARX 230637
AFDARX
Area Forecast Discussion
National Weather Service La Crosse WI
135 AM CDT Tue Sep 23 2025
.KEY MESSAGES...
- Seasonable conditions the rest of the week with temps generally
at/few degrees above the normals. Trending dry.
&&
.DISCUSSION...
Issued at 135 AM CDT Tue Sep 23 2025
Closed upper level low hanging over lake Superior in the overnight
while associated trough axis hangs westward across northern MN.
NAM/GFS/EC all slowly sink this tandem south over the next couple
days, eventually nudging east Thu afternoon as an upper level ridge
starts to push over the plains.
The GEFS and EPS then lean into a progressive flow for the rest of
the week, sliding the ridge across the upper mississippi river
valley by Friday with a shortwave set to track across southern
Canada/northern parts of region for the weekend. Broad ridging then
favored moving into next week, although there are differences
between the GEFS and EPS in this stead.
> PRECIPITATION CHANCES:
Despite the presence of the cyclonic flow a loft, and a lobe of
shortwave energy set to rotate across the area, short-medium range
guidance not bullish on any threat for rain over the next couple
days. Saturation seems to be the biggest issue while soundings
suggest some low level capping concerns. Normally, this kind of
synoptic setup would favor at least low end rain chances (20-30%) for
afternoon showers. For now, will lean into the dry forecast favored
by the short term/model blends and monitor trends.
While the late week trough is currently favored to hold north of the
local area, it is progged to drag a cold front south of it. Not much
QPF response in the vast bulk of the GEFS and EPS members - again
tied to saturation concerns (lack there of).
> TEMPERATURES:
There will be some "up and down" to the temperatures over the next 7
days or so, but no significant warm up or cool down currently
expected. Mostly, temps fluctuate in the 70s (at or a few degrees
above the late Sep normals) - although some locations could push 80
degrees on a few days.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1245 AM CDT Tue Sep 23 2025
Fog will be the primary concern across the region throughout the
overnight and into the morning hours as relatively light winds and
recent rainfall will lead to a favorable environment for fog
formation. The one question that remains for how widespread fog
development will be is on how cloud trends will manifest over the
coming hours. However, given the fairly high probabilities (50-80%)
in the recent HREF across southeast MN for 1/4SM, have opted to
include mention of VLIFR fog at KRST with probabilities at KLSE
being much lower (10-30%) so kept visibilities slightly higher.
Fog will likely persist through around 13-15z before mixing out
later into the morning leaving behind VFR conditions for much of the
daytime hours. Winds will generally remain light around 5 kts or
less from the north/northeast throughout much of the TAF period.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...None.
MN...None.
IA...None.
&&
$$
DISCUSSION...Rieck
AVIATION.....Naylor

NWS ARX Office Area Forecast Discussion