Lolo, Montana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

174
FXUS65 KMSO 271836
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1236 PM MDT Fri Jun 27 2025

.DISCUSSION...

KEY MESSAGES:

- Scattered showers and thunderstorms through this evening across
  southwest Montana, near the Divide.

- Warming and drying trend Sunday into early next week, with
  temperatures 10-15F above normal.

- Shower and thunderstorm activity returns Tuesday, becoming more
  widespread, especially along and south of I-90.

GOES Satellite early this afternoon highlights a blossoming
cumulus field across Lemhi County, ID and southwest MT, where the
best axis of moisture and instability is present. Radar trends
match closely with high resolution model guidance projecting
scattered shower and isolated thunderstorm activity near the
divide in southwest Montana. This will continue to be the trend
through this evening, with gusty outflow winds up to 40 mph being
the primary concern with any thunderstorm activity.

On Saturday, shower activity will focus across northwest Montana,
mainly in Flathead County, as a upper level disturbance moves
across southern Alberta. Limited atmospheric instability will
limit thunderstorm development, however, an isolated storm or two
can`t be ruled out across Glacier Park Saturday afternoon and
evening. Breezy westerly winds will develop area wide with the
aforementioned disturbance, with gusts of 20-25 mph across valley
areas.

Ensemble model guidance remains in strong agreement for a ridge of
high pressure to settle across the region Sunday into early next
week. A warming trend is expected, with temperatures rising
10-15F above normal by Monday next week.

Showers and thunderstorms return Tuesday next week, with activity
becoming more widespread Wednesday under a south-southwest flow
pattern. Ensemble guidance has been consistent the last few days
highlighting a surge of subtropical moisture across the Great
Basin into the Northern Rockies, with atmospheric moisture
climbing 125-150% of normal by Wednesday. This flow pattern will
be aided by a ridge of high pressure centered near the Four
Corners region and a closed low forming over California, seen
within deterministic runs of the 12z GFS/ECMWF. A deeper dive into
instability suggests the potential for a few stronger
thunderstorms capable of producing heavy rain and small hail given
the anomalously high atmospheric moisture. The lack of an
organized mid-upper level jet will limit wind shear and the
potential for organized long-lived severe convection.


&&

.AVIATION...A growing cumulus field is seen in GOES Satellite
imagery this afternoon, with scattered showers forming across
southwest Montana near the divide. Model guidance has been
trending convection eastward with recent model runs, with storms
projected to form along the divide in southwest Montana between
27/2000-2200Z, before quickly shifting eastward. Limited
confidence (<20% probability) exists for any storms in the
vicinity of KBTM through this evening. Confidence is high for
widespread gusts of 15-25kts across most terminal sites through
28/0200Z this evening as an upper level disturbance passes.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$