Ahsahka, Idaho Weather Forecast Discussion

631
FXUS65 KMSO 151856
AFDMSO
Area Forecast Discussion
National Weather Service Missoula MT
1256 PM MDT Mon Sep 15 2025
.DISCUSSION...
KEY MESSAGES:
- Showers ending this evening, other than along the Continental
  Divide
- Trend towards warmer and drier weather through the rest of the
  work week, with morning frost and fog possible
- Return of showers and thunderstorms possible this weekend
The slow moving low pressure system will continue to shift into
south-central Montana through tonight. A persistent band of
precipitation wrapping around the low into northwest Montana near
the Canadian border will gradually diminish, along with general
showers further south. The one exception will be along the
Continental Divide, where lingering shower activity will likely
continue into Tuesday.
With the low pressure system shifting eastwards, forecast models
depict clearing skies tonight, especially across northcentral
Idaho. Sometimes our models depict this clearing occurring a
little too quickly, but areas that do see clearing will likely see
fog develop by Tuesday morning, especially for locations that had
significant precipitation over the last 48 hours.
High pressure building over the Intermountain West Tuesday through
the end of the work week will bring a shift back to warmer and
drier weather. Cool mornings will give way to warm afternoons. Fog
and even some frost will be possible each morning, especially in
the higher elevation valleys near the Continental Divide.
Forecast models are beginning to show a flattening of the ridge
over the weekend, though there are some disagreements on the
timing of this occurring. As the ridge flattens, increasing
westerly winds and potential for showers and thunderstorms will
increase.
&&
.AVIATION...The upper level low will slowly shift into south-
central Montana through tonight. For most areas, precipitation
will taper later this evening, though showers are expected to
linger along the Divide into Tuesday. Showers will increase near
BTM after 16/1000z, with lowered ceilings and temporary visibility
reductions under rain showers. Widespread obscurations of the
terrain will linger into Tuesday morning due to a low to mid level
cloud deck. Patchy valley fog development is likely Tuesday
morning, especially from the US-93 corridor westward where
overnight clearing is most likely.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&
$$

NWS MSO Office Area Forecast Discussion