265
FXUS65 KMSO 031932
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
132 PM MDT Wed Jul 3 2024

...A Northern Rockies Heatwave Likely July 5-12...

.DISCUSSION...With a lack of atmospheric convective inhibition,
storms have developed quickly this afternoon. Water vapor
satellite loops show a well-defined cyclonic circulation moving
north to south through northwest Montana, which will further aid
in thunderstorm development. Brief heavy rain is expected under
storm cores, and there is enough lift for isolated hail.
Thunderstorm coverage is expected to decrease through the evening.
Temperatures will return to near normal on Thursday, with fewer
storms than today.

Confidence remains high that an extended period of heat will
start this weekend and continue well into next week. The middle of
next week looks to be the hottest period, with valleys in central
Idaho hitting the 100-115 degree range and western Montana
valleys reaching 90-105 degrees by next Wednesday (July 10th).
Nighttime temperatures are expected to cool only into the 50s to
60s, which will make it difficult for those without air
conditioning or other means of cooling down to find respite from
the heat. Please check on the elderly, those susceptible to
heat,and protect all animals and livestock during this stretch of
hot temperatures.

An aspect that is less certain during this period of hot
temperatures is the thunderstorm forecast. The latest model
guidance trends toward thunderstorm chances on Saturday in western
Montana, especially along the Divide.


&&

.AVIATION...Similar to the past two days, thunderstorms continue
to develop across western Montana, with increased coverage
compared to yesterday. These storms are closely associated with a
well-defined circulation moving from north to south through the
afternoon and evening. Radar projections indicate most storm
activity will be concentrated from KGPI to KMSO to KBTM and
eastward into the evening, with brief heavy rain under storm
cores. Patchy fog is possible Thursday morning.


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...     Excessive Heat Watch from Tuesday afternoon through Wednesday
     evening for Kootenai/Cabinet Region...Lower Clark Fork
     Region.

ID...Excessive Heat Watch from Monday afternoon through Wednesday
     evening for Northern Clearwater Mountains...Southern
     Clearwater Mountains.

     Excessive Heat Watch from Sunday afternoon through Wednesday
     evening for Lower Hells Canyon/Salmon River Region...
     Orofino/Grangeville Region.

&&

$$