426
FXUS65 KMSO 020826
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
226 AM MDT Tue Jul 2 2024

.DISCUSSION...Showers and thunderstorms will focus across
northwest Montana, especially in Flathead County and Glacier Park,
this afternoon and evening. Thunderstorms are expected to develop
between 12:00 and 2:00 pm MDT, with probabilities reaching 40-60%
across Glacier Park through 8:00 pm. These storms could produce
brief heavy rain, with localized rates up to 0.50 inches per hour,
as atmospheric moisture levels are 125-150% of normal. Cloud
cover this morning will clear in the afternoon along and south of
I-90, leading to generally clear skies with westerly breezes of
15-25 mph.

The coverage of showers and storms will expand to include all of
western Montana and the Clearwater Mountains on Wednesday. Another
trough embedded within northwesterly flow will provide modest
atmospheric instability (CAPE 100-250 J/kg) and lift for shower
and storm development. Similar to Tuesday, the primary focus for
shower and storm activity will be in Flathead County and Glacier
Park, with 24-hour probabilities for 0.25 inches of precipitation
reaching 60%.

On Independence Day, Thursday, a general drying trend is expected
across the area, with isolated showers and storms developing
along the divide. Highs will warm into the 70s and 80s across
western Montana and into the lower 90s in the lower valleys of
north-central Idaho under mostly clear skies.

Confidence is high for a hot and dry pattern from Friday into the
weekend and beyond. Ensemble models are in strong agreement (>90%
of members) with a high-amplitude ridge moving across the Pacific
Northwest from Friday into Sunday, with the ridge axis shifting
over the Northern Rockies by next week. Ensembles have been
indicating a longer-duration heatwave across the lower elevations
of Idaho in particular. This trend is well-reflected in the NBM
guidance, with probabilities for temperatures of 100F or greater
exceeding 50% in Orofino and Riggins each day between July 6 and
10. Several days of temperatures between 90-95F or greater will
also impact valley areas of western Montana. Now is the time to
prepare for potential heat impacts! /Lukinbeal

&&

.AVIATION...
Showers and thunderstorms will return to northwest Montana,
particularly in Flathead County, this afternoon and evening.
Thunderstorms are expected to develop between 02/1800-2000Z and
continue through 03/0300Z. These storms could produce brief heavy
rain, with localized visibility reductions below 2SM under storm
cores. Cloud cover this morning along and south of I-90 will clear
this afternoon, with westerly wind gusts increasing to 15-25
knots across western Montana. /Lukinbeal

&&

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

$$