Area Forecast Discussion
Issued by NWS Missoula, MT
FXUS65 KMSO 062050
Area Forecast Discussion
National Weather Service Missoula MT
250 PM MDT FRI MAY 6 2016
.DISCUSSION...Breezy east winds will continue throughout the
afternoon and evening for western Montana, with generally mild
temperatures. Lemhi county and southwest Montana will see rounds
of showers as a low pressure spins to our south.
A drier and warmer easterly flow will influence
much of western Montana and north central Idaho on Saturday.
Temperatures should again warm to 10 to 15 degrees above normal.
The exception will be mainly in Lemhi County where the moisture,
instability, and a few showers should persist.
Sunday should be a transition day with generally warm and dry
conditions through much of the day. However, some moisture and
instability may develop across west central and southwest Montana
in the afternoon, which could cause isolated showers and
thunderstorms. As a cold front approaches late in the day,
southwest winds will increase. Temperatures are expected to be at
least 10 degrees above normal Sunday.
A cold, wet low pressure will slide south from Canada into our
area by Monday morning. Widespread precipitation (snow above
roughly 5000 feet) will begin first in northwest Montana,
spreading over the rest of western Montana and north central
Idaho throughout the day. High temperatures will be markedly
cooler than Sunday, by about 20 degrees. Showers continue Tuesday
morning, especially along the Continental Divide, where snow
levels will again be low, between 4500 to 5500 feet. Communities
such as Butte, Anaconda, and Georgetown Lake could see snow
showers, which would be heavy and wet. Forecast confidence in
this occurring is moderate at this point, and we will continue to
refine snow level and amount details in the coming days.
Wednesday morning will be chilly after clouds begin to clear in
northwest flow, so frost and freeze are a possibility. Again,
details are uncertain this far out, but it will be a situation
worth monitoring for those with sensitive vegetation. The rest of
next week looks to bring periodic weak weather disturbances.
.AVIATION...A moderate to strong easterly flow will continue
tonight. Moisture will continue to bank up along the Continental
Divide and occasionally surge across Lemhi County and far
southwest Montana. This should translate into scattered mountain
obscurations and a few light showers for sites such as KSMN.
Further to the north over west central/northwest Montana and the
Camas Prairie, the air mass should slowly dry and clouds gradually