Area Forecast Discussion
Issued by NWS Missoula, MT
FXUS65 KMSO 300945
Area Forecast Discussion
National Weather Service Missoula MT
345 AM MDT SAT APR 30 2016
.DISCUSSION...A broad trough continues to linger over the majority
of the United States as an embedded weak low circulates over the
Northern Rockies. This feature will continue to cause light
precipitation through the day. The current focus of precipitation
is moving through southwest and west central Montana. This band
of precipitation will drift to the west then become widespread
convective showers by the afternoon. An isolated thunderstorm
could develop across southwest Montana and Lemhi county this
afternoon. Another area of precipitation is currently over
eastern Washington and will migrate southward into portions of
north central Idaho. Temperatures for today should be running near
normal for most locations. The exception will be southwest Montana
into Lemhi county where temperatures appear to be 5 to 10 degrees
Showers should be steadily diminishing through out the night
tonight. The models are indicating that easterly winds could mix
down to surface over Flathead Lake this evening creating gusty and
choppy conditions. Wind gusts up to 30 mph will be possible during
the evening hours, impacting boaters on the lake.
High pressure will steadily become the dominant feature over the
Northern Rockies on Sunday through the first part of the week.
This ridge will cause a drying and warming trend for the region.
Temperatures should be running 5-10 degrees above normal by Monday
An upper level trough approaching the Pacific Northwest will
increase southwesterly flow Tuesday-Thursday allowing warm
temperatures to continue with highs well into the 70s and low 80s
for many valley locations. Moisture will also be on the increase
for a growing threat of showers and thunderstorms, especially
Wednesday into Thursday.
The main energy with the trough will drop down the West Coast then
slowly push through the Desert Southwest Friday into next weekend.
This will leave the Northern Rockies in easterly flow leading to
seasonably cool temperatures and showery conditions.
.AVIATION...A swath of light precipitation will continue to move
through southwest and west central Montana this morning. This
precipitation will cause low ceilings especially at KMSO and KBTM
through mid morning. Then the precipitation will become widespread
convection by the afternoon. A low threat exists for thunderstorms
near KSMN and KBTM during the late afternoon and early evening