Area Forecast Discussion
Issued by NWS Missoula, MT
FXUS65 KMSO 302041
Area Forecast Discussion
National Weather Service Missoula MT
240 PM MDT MON MAR 30 2015
...Turning cooler again and very unsettled/variable conditions
.DISCUSSION...High pressure and relatively warm/dry conditions
will persist through tonight.
A cold front is expected to move across north central Idaho
Tuesday morning and then intensify as it marches across western
Montana Tuesday afternoon. The intensifying cold front and cold
air surging into the region will produce moderate to strong winds.
The strongest winds should be in southwest Montana and Lemhi
County in the afternoon. However, significant winds should also
impact Flathead Lake with rough wave conditions.
Much cooler air is expected to surge into the region behind the
front with snow levels lowering to most valley floors by Tuesday
night. However, the showers should be on the decrease by Tuesday
night with only light snow accumulation expected over mountain
passes. The valleys could also see scattered light snow or a
rain/snow mix, but the showers should be quite light with little
or no accumulation.
A rather cold weather system is expected to remain over the
northern Rockies Wednesday and Thursday. Compared to Monday,
afternoon temperatures should be 20 to 25 degrees colder Wednesday
and Thursday. Overnight temperatures should also be quite cool
with a hard freeze expected many areas and some possible impacts
to early budding/developing plants and any above ground
irrigation that has been started. The atmosphere will not be
overly moist, but probably unstable enough to support scattered
snow/graupel showers especially in the afternoons. Local snow
accumulations are also possible over most mountain passes.
A cool and showery pattern will continue Friday through early next
week. Minor disturbances will pass across the region bringing
scattered rain/snow showers from time to time, although there will
be nice conditions between the disturbances. Models have trended
toward the potential for a stronger disturbance on Easter into the
following Monday, which could lead to more widespread snowfall but
confidence is low at this time. Also, temperatures will remain
below normal with morning lows especially chilly continuing the
threat to sensitive vegetation.
.AVIATION...Fair conditions will continue tonight with high/mid
level clouds increasing by early Tuesday ahead of a cold front.
An increasing pressure gradient ahead of the front will allow for a
gradual increase in southwesterly winds on Tuesday morning with
gust to 30-35 kt at area terminals during the afternoon. Showers
and perhaps an isolated thunderstorm will also become a concern by
late morning at KGPI and in the afternoon hours for KMSO, KBTM,