463
FXUS65 KMSO 300858
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
258 AM MDT Sun Jun 30 2024

.DISCUSSION...A Pacific trough of low pressure is currently moving
across eastern Washington this morning, spreading light to
moderate rain showers over northern Idaho. The focus of the
precipitation this morning and afternoon, continues to favor
Clearwater County in Idaho, and northwest Montana from Mineral,
Sanders, Lincoln, Lake and Flathead counties. These locations will
have around a 60% probability of picking up at least 0.25" of
rainfall by sunset this evening. Isolated areas, particularly in
the higher terrain may see slightly higher amounts.

Later this afternoon and early evening a surface low will develop
just east of the Continental Divide. This, along with increased
instability from afternoon heating, is expected to allow for the
development of strong thunderstorms in Deerlodge, Powell, and
Sliver Bow counties. Currently, the Storm Prediction Center has
these areas under a marginal risk for severe thunderstorms. High-
resolution models suggest storms will develop between 3:00-7:00 PM
MDT before moving east of the divide. Those planning outdoor
activities should be prepared for lightning, gusty winds, and
small hail. Any severe thunderstorms (5% probability) that do
develop, will be capable of producing quarter to half dollar size
hail, along with damaging wind gusts.

The Northern Rockies will remain in a northwesterly flow pattern
through mid-week, that will maintain seasonal temperatures with
highs ranging from the 70s to 80s. Daily showers and
thunderstorms are expected to develop, with convective activity
focused along the Continental Divide.

By the end of the week and upcoming weekend, 80% of ensemble
guidance continues to show the return of a ridge of high pressure.
This will likely lead to above-normal temperatures and below-
normal precipitation for the region.

&&

.AVIATION...A Pacific trough of low pressure will bring light to
moderate rainfall to portions of north-central Idaho and
northwest Montana later this morning through the afternoon.
Rainshowers will periodically reduce visibility and ceilings for
KGPI between the hours of 30/1400Z-30/2000Z. Currently, there is
a 50% probability for thunderstorms for KGPI, KMSO, and KBTM from
30/2100Z-01/0300Z this evening, that may bring brief periods of
gusty winds, small hail and heavy rainfall. High-resolution models
suggests the majority of the convection will move east of the
Continental Divide by 01/0300Z this evening.

&&

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

$$