062
FXUS63 KFGF 111141
AFDFGF

Area Forecast Discussion
National Weather Service Grand Forks ND
641 AM CDT Sat Oct 11 2025

.KEY MESSAGES...

- Near critical fire weather conditions are expected across
  northwest and west central Minnesota this afternoon and early
  evening.

- Showers and isolated thunderstorms are expected tonight
  through Sunday night with potential impacts to outdoor
  activities.

- A period of strong winds may impact locations along and west
  of the Red River Valley Sunday afternoon through Sunday night.
  There is a 30 percent chance for wind gusts greater than 45
  mph during that period.

&&

.UPDATE...
Issued at 641 AM CDT Sat Oct 11 2025

A few high based showers have moved into northeast ND, however
the dry layer is limiting what is reaching the surface with
reports of only a trace so far where these have tracked
(sprinkles/virga). As instability increase later a few high
based non severe thunderstorms may also develop, however the
dry layer in the lower atmosphere isn`t likely to become
saturated until much later. This of course raises the potential
for dry lightning and we will want to monitor that in MN where
near critical fire weather conditions are still forecast to
occur in the afternoon/early evening. Forecast remains on track,
so only minor adjustments were made to near term trends.

&&

.DISCUSSION...
Issued at 337 AM CDT Sat Oct 11 2025

...Synopsis...

SW flow is beginning to build into the High Plains of the Dakotas
while the mid/upper ridge axis shifts east and the upstream trough
continues to move east into the western US. Broader/longwave
troughing eventually settles in across the Western US, with a
negatively tilted shortwave and mid/upper low moving across the
Northern Plains and Canadian Prairies later tonight through Sunday
night. This eventually moves east into the Hudson Bay region mid
week and deepens. Longwave troughing persists across the western US
through the forecast period along with ridging in the southern US,
resulting in a short lived blocking type pattern during the middle
and later part of the week. Our CWA remains on the northern split of
the flow in this pattern until SW flow and eventual troughing shifts
east once again. The general temperature trends will be favoring
above average temperatures through Sunday, followed by much cooler
temperatures in the post frontal air mass and northwest flow early
in the week. There will be limited moderation towards the end of
next week back towards generally mild/seasonal temperatures.

Besides this weekend rain event with the initial mid/upper low
passage there is much more uncertainty on rain chances/timing as
embedded impulses will tend to be weaker/progressive within the flow
around the ridge to our south and west until the main long wave
trough begins to transition east late week and next weekend.
Ensembles continue to show a larger spread in how that trough
eventually shifts east, though impacts even on the clusters that
support more organized precipitation chances impacts would just be
related to rainfall (temperature profiles still too warm for early
season winter precip impacts).

...Near critical fire weather this afternoon/early evening...

A very dry air mass in in place over our region ahead of the
approaching trough. Higher level clouds cover could eventual impact
mixing potential this afternoon, however considering the magnitude
of dry air in the lowest 10kft even after cloud cover increase aloft
Tds should fall to the upper 20s/lower 30s across northwest MN
while moist flow building in aloft gradually brings increasing Tds
from the west. Winds within the mixed later support 15-25 mph
sustained winds along and west of the RRV with gusts around 35 mph.
Winds may not be quite as strong to the east of the valley but RH is
more likely to remain under 30% and wind gusts would still reach 25
mph at times through the afternoon/early evening. SPS was issued to
cover these impacts. if cloud cover holds off, temperates fall
closer to 70, and Tds drop closer to 25 then RFW conditions have a
chance to occur (20% based on current guidance).

...Rain and isolated thunderstorms tonight through Sunday night...

Initially the deep dry air in place will limit rain reaching the
surface today, with virga or a few sprinkles until more organized
forcing and deeper moisture advection arrives later this evening.
Anomalous PWATs and instability are still forecast to be in place
through Sunday, and there continues to be a strong signal for a
large area of light rain showers with progressive clusters and
isolated thunderstorms as WAA aloft overspread of our CWA tonight
through Sunday and the main mid/upper low transitions into southern
Manitoba. A dry slot does eventually move into eastern ND which will
play a role in limiting coverage in our west during the day Sunday,
though showers are more likely to linger into the evening in MN.
Light rainfall 0.1-0.25" is expected across much of our region
through Sunday, with the best chance for 0.5" or higher (50%) from
the southern RRV and across northwest MN.

...Strong winds Sunday afternoon into Sunday night...

A strong cold front moves into the region with a signal for
strong CAA/6hr pressure rises coinciding with the arrival of
the dry slot and PV anomaly/strong subsidence late Sunday
afternoon through the evening hours. Immediately ahead of this
strong gradient and increased mixing in southerly flow could
allow for a few gusts in excess of 40 mph in the RRV. However,
the main period of concern will be along and behind the cold
in the late afternoon/evening. Model soundings support a period
of 45 mph+ gusts and some deterministic model profiles along
and west of the RRV actually show max winds at the top of the
mixed layer around 50kts which could support brief/localized
gusts around 58mph (warning). ECMWF EFI shows values generally
around 0.7 in our CWA (advisory) with 0.8 values (which are a
good indication of warning impacts) to our northwest. Ensemble
probabilities based on combined raw ensembles (LREF) and NBM are
20-30%. As the timing of the frontal passage may remain closer
to sunset as low levels begin to decouple the duration of
impacts may be shorter and tied to the immediate frontal
passage. This is still a period to monitor.

&&

.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 641 AM CDT Sat Oct 11 2025

VFR conditions should prevail across eastern ND and northwest
MN through this evening, with increasing southeast winds (gusts
20-30kt). A few high based showers/virga may move through the
region through the early evening, but a deep dry layer in place
is limiting coverage/impacts. Widespread rain showers and
eventual MVFR conditions overspread the region as deeper
moisture arrives late evening into the overnight period.
Isolated thunderstorms may also develop in the region, however
probabilities at TAF sites are less than 30%. A strong LLJ
40-50kt develops this evening as well, which may result in a
period of low level wind shear (transitioning west to east
through the night).

&&

.FGF WATCHES/WARNINGS/ADVISORIES...
ND...None.
MN...None.

&&

$$

UPDATE...DJR
DISCUSSION...DJR
AVIATION...DJR