Elk Mound, Wisconsin Weather Forecast Discussion

033
FXUS63 KMPX 200802
AFDMPX
Area Forecast Discussion
National Weather Service Twin Cities/Chanhassen MN
302 AM CDT Sat Sep 20 2025
.KEY MESSAGES...
- Isolated showers return this afternoon and evening, with lower
coverage and duration than Friday.
- Dry weather returns for most of the week with seasonal
  temperatures.
&&
.DISCUSSION...
Issued at 302 AM CDT Sat Sep 20 2025
The upper level low parked over the region is readily apparent
in GOES-East Differential Water Vapor satellite imagery this
morning, with the bulk of Minnesota, Iowa, and Wisconsin all
seeing swirling cloud cover as a result. Scattered showers and
weak thunderstorms continue to persist over portions of
Wisconsin, however mainly east of the MPX CWA favoring central
to eastern Wisconsin with the last few showers moving through
Rusk and Chippewa counties for us. CAMs show a fairly quiet day
through the late afternoon to early evening, at which point
isolated showers and weak storms once again become possible as
the upper level low continues to churn across the region. The
upper level low looks to weaken with the primary forcing
remaining being any lingering mid-level vorticity and what is
left of a surface response, resulting in sporadic showers that
should only produce a few tenths of an inch in any one location
as they move through. Sunday could also see some lingering
showers as the upper level occlusion finally pushes eastwards
over the Great Lakes, with the lower resolution synoptic
guidance generally favoring showers more than the shorter range
high resolution guidance for portions of Sunday. We likely see
at least a few showers, but overall coverage will be lower than
both today and Friday with limited accumulation.
As the upper level system pushes eastwards over the eastern CONUS
through midweek, a broad area of north to northeasterly upper level
flow will bring weak subsidence and weak surface high pressure to
the region covering the remainder of the forecast period. This will
generally keep us dry with little chances for rain, however fair
weather cloud cover will keep us from seeing total sunshine. The
upper level pattern flips back to northwesterly later in the week
with surface high pressure lingering, with significant model
differences once you reach Friday such that low confidence arrives
by next weekend in terms of the forecast. Ensemble guidance also
shows a significant split between dry and rain chances, especially
apparent within the GEFS with significant split in membership.
Taking a look at the deterministic runs, the differences are stark
with an occluded upper level low sitting over the southern Great
Lakes within the GFS which does not exist within the CFS/ECMWF, with
the CFS favoring weak upper level flow and the ECMWF showing
northwesterly flow aloft. Until these differences get resolved,
there is little confidence in tracking even synoptic scale features
beyond running a near-normal temperature forecast, with low to mid
70s persisting through the week and into the weekend. Overall, there
is not much to discuss weather wise beyond the rain chances through
the next few days as we transition from September to October. The
autumnal equinox is only a few weeks away, and we will rapidly begin
losing additional daylight as it arrives on top of the hour or so of
daylight we have already lost in September.
&&
.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 145 AM CDT Sat Sep 20 2025
Precipitation is mainly confined to western WI at initialization
but the grander scheme is to have fog and low stratus prevail
through sunrise and into the first half of Saturday. Little in
the way of additional precipitation is expected, potentially
late afternoon with some isolated to scattered showers/t-storms
but the driving factor to flight conditions Saturday will be the
fog/stratus. Conditions will likely remain degraded until late
Saturday night into Sunday.
KMSP...While conditions start as VFR, some bouncing to IFR is
likely through sunrise with more stable conditions overnight but
trapping low level moisture in the form of low stratus.
Conditions improve late morning onward, but peak daytime heating
may contribute to instability-driven diurnal
showers/thunderstorms. Nothing widespread or long-lasting is
expected, but enough to maintain the PROB30 mention.
/OUTLOOK FOR KMSP/
SUN...Chc MVFR/-TSRA, mainly P.M. Wind W 5-10 kts.
MON...Mainly VFR. Slight chc MVFR/-SHRA. Wind variable 5 kts.
TUE...Mainly VFR. Wind NE 5-10 kts.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...None.
WI...None.
&&
$$
DISCUSSION...TDH
AVIATION...JPC

NWS MPX Office Area Forecast Discussion