National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

527
FXUS65 KMSO 211030
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
430 AM MDT Fri Sep 21 2018

.DISCUSSION...

A weak ridge of high pressure will be present over the Northern
Rockies through midday Saturday. Conditions will be mostly dry
and warm, with the exception of northwest Montana. For northwest
Montana, passing rain showers will exist through today.

On Saturday, southwest flow aloft will increase across the
Northern Rockies. The strong flow at ridgetops is expected to mix
down to the valleys, with gusty winds developing. Wind gusts over
30 mph will be common during Saturday afternoon across southwest
Montana. Thunderstorms area possible for Saturday afternoon. Otherwise
and elsewhere, rain shower activity will increase throughout
Saturday and Sunday. Snow levels will lower to 6500 feet along the
Continental Divide for a brief time Sunday night.

Tuesday through the end of next week, northwest flow will be
present over the Northern Rockies. A series of storm systems will
move through the upper level flow and skirt the Continental
Divide, with most rain shower activity east of the Divide.

Some global weather models suggest that a relatively cold storm
system will move west of the Continental Divide next weekend,
however there has been a lot of inconsistency among each model
run. There is low confidence of an early Fall cold outbreak
occurring next weekend.

&&

.AVIATION...VFR conditions will prevail over most the area.
Around 9/21 1500Z, slight possibility of passing showers from
KGPI to the Continental Divide until 1800z. Afternoon mixing could
bring gusty westerly winds to higher elevations along the Divide
and south as far as central Idaho mountains.


&&

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

$$