305
FXUS65 KMSO 062003
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
203 PM MDT Sat Jul 6 2024

.DISCUSSION...The Northern Rockies is under northwesterly flow
this afternoon which will cause some gusty northwesterly winds
and a few showers along the Continental Divide.

A ridge of high pressure builds over the region Sunday through
much of next week. This ridge will cause excessive heat over the
Northern Rockies. The valleys of north central Idaho have an 80 to
100% probability of having temperatures of 100 degrees or higher
on Wednesday. While Montana valleys west of Highway 93 generally
have a 50 to 80% chance of breaking into the century mark on
Wednesday afternoon. The combination of extremely hot days along
with warm nights, especially in the valleys of north central
Idaho, will create hazardous heat conditions so Excessive Heat
warnings and advisories have been issued.

A subtle disturbance moves through the region Wednesday into
Thursday which will flatten the ridge slightly. This feature will
have minimal impacts on the temperatures, but the increase in
westerly winds is anticipated.

A second disturbance is expected to move along the Canadian border
next weekend. This feature will cool temperatures slightly along
with the potential for a few showers and thunderstorms to develop
across southwest Montana during the afternoon and evening.

&&

.AVIATION...The Northern Rockies will be under northwesterly flow
this afternoon and evening. This flow pattern will keep gusty
northwesterly winds at area terminals. The majority of western
Montana will experience scattered cumulus clouds until sunset with
the potential of a few showers developing along the Divide this
afternoon. The clouds and winds will begin to diminish around
07/02z.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Heat Advisory from 1 PM Tuesday to midnight MDT Friday night for
     Flathead/Mission Valleys...Kootenai/Cabinet Region...Lower
     Clark Fork Region...Missoula/Bitterroot Valleys.

ID...Heat Advisory from noon Tuesday to 11 PM PDT Friday for Northern
     Clearwater Mountains.

     Excessive Heat Warning from noon Tuesday to 11 PM PDT Friday for
     Orofino/Grangeville Region...Southern Clearwater Mountains.

     Excessive Heat Warning from noon Monday to 11 PM PDT Friday for
     Lower Hells Canyon/Salmon River Region.

&&

$$