Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Missoula Montana
248 PM MDT Sat Oct 22 2016
..a rarity this october: drying, mild through Monday...
Relatively warm and increasingly dry conditions will be present
across the northern rockies through Sunday. Considering the
clearing skies and recent rainfall across the region, patchy fog
will develop for some valleys of western Montana and north central
Idaho late tonight through Sunday morning. Despite a patchy
coverage of fog, visibility can change suddenly for those
traveling during this time. Clouds are expected to increase once
more on Sunday morning, however dry and mild conditions will be
evident Sunday afternoon.
Our next weather system will begin impacting the region late Monday
night into Tuesday morning. Snow levels are expected to be above
pass levels near 7000 feet, due to a warm southwesterly flow
ahead of the approaching front. At this time, northwest Montana
and north-central Idaho will see the most precipitation, though
precipitation amounts will be much lower than with the previous
weather systems we have been experiencing. With some heating
during the day on Tuesday, scattered rain showers will likely
develop over the rest of the region in the warmer unstable
air ahead of the cold front.
As soon as the Tuesday cold front moves south and east out of the
region, another surge of moisture will be on its heels for
Wednesday. Forecast models have slowed the progression of the
shortwave, so pushed back on the rain probabilities until later in
the day on Wednesday. Again, with this particular weather pattern,
snow levels will remain above Mountain Pass levels. As with the
previous cold front, the majority of the precipitation will remain
in northwest Montana, north of I-90. Showers will likely linger in
northwest Montana through the day on Thursday, with the rest of
the region enjoying a relatively warm southwesterly flow. In
saying that, with the exception of northwestern Montana, most
areas will see slightly above normal temperatures in the mid 50s
low 60s during the week next week.
In the long term, models continue to show unsettled weather with
near or slightly above normal temperatures and chances of showers
Aviation...patches of valley fog will be the most significantly
impactful weather present over northern rockies air space during
the next 24 hours. The fog will be greatest 23/0900z through
23/1600z, possibly impacting areas near terminals kmso and kgpi.
Otherwise, few other significant changes to flying weather
expected during this time.