845
FXUS65 KMSO 201012
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
412 AM MDT Mon May 20 2024

.DISCUSSION...The Northern Rockies will be under weak
northwesterly flow today through Tuesday. This flow pattern will
keep temperatures cooler than average for this time of year. The
atmosphere is expected to become unstable enough for the
development of scattered to numerous showers this afternoon.

The models are still indicating a significant low pressure system
moving through the region Wednesday into Thursday. This low will
bring widespread precipitation and even cooler air. Snow levels
are still anticipated to drop to around 5,000-6,000 feet by
Thursday morning. The latest progression of the low would bring
significant snow to the higher terrain of north central Idaho and
southwest Montana. Lost Trail Pass, William Creek Summit and
Georgetown Lake region have a 40-60% chance of receiving over 2
inches of snow by Thursday morning and a 20-40% chance for more
than 4 inches. This snow will make for difficult traveling during
the overnight into the early morning hours on Thursday.

A weak ridge builds over the region Friday causing a slight
warming and drying trend. This ridge will be short lived as all
model clusters are showing another low pressure system impacting
the Northern Rockies on Saturday. After the passage of this
system, models are trending towards a ridge of high pressure
building over the region by the first part of next week.

&&

.AVIATION...A few weak showers continue to move across north
central Idaho early this morning. While other portions of the
region are having patchy fog and low stratus develop due to
yesterday`s precipitation. The fog and stratus is expected to
diminish during the morning hours. This afternoon scattered to
numerous showers are expected producing period of reduced
visibility due to precipitation along with gusty erratic winds.


&&

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

$$