Lewiston, Minnesota Weather Forecast Discussion

847
FXUS63 KARX 231055
AFDARX
Area Forecast Discussion
National Weather Service La Crosse WI
555 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 /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 555 AM CDT Tue Sep 23 2025
LIFR fog will continue over the next couple hours north of the IA/MN
state line this morning which has resulted in vsbys of 1/4SM in
numerous locations. As we head towards mid-morning, increasing
diurnal mixing will slowly allow this fog to lift into a low-level
stratus deck before clearing to VFR by afternoon. Uncertainty
remains as to how long category reducing cigs will remain through
the morning but given that the NBH has decent probabilities for MVFR
cigs to persist through at least 18z at KLSE and KRST, have held
onto some MVFR cigs through that period. Otherwise, VFR conditions
are expected by the afternoon with winds remaining at around 5 kts.
Some fog potential is once again hinted at tonight and towards 12z
on Wednesday in deterministic guidance, however confidence in how
this would manifest remains low at this time.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...Dense Fog Advisory until 9 AM CDT this morning for WIZ017-029-
     032>034-041-042-053.
MN...Dense Fog Advisory until 9 AM CDT this morning for MNZ079-
     086>088-094>096.
IA...None.
&&
$$
DISCUSSION...Barendse
AVIATION...Naylor

NWS ARX Office Area Forecast Discussion