Area Forecast Discussion
Issued by NWS Great Falls, MT

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FXUS65 KTFX 240954
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
354 AM MDT Mon Apr 24 2017

.DISCUSSION...

Today through Tuesday...Mostly cloudy skies and periods of
precipitation will prevail across the CWA as multiple shortwave
troughs move generally eastward over the region. The first primary
shortwave trough looks to impact Southwest MT this afternoon through
Tuesday morning, while the second primary disturbance should skirt
the international border and Hi-Line Tuesday afternoon. In general,
snow levels should fluctuate between approximately 5000 and 6000
feet MSL during the period. While most mountain passes should
receive minor snow accumulations, decided to issue a winter weather
advisory for Targhee Pass and West Yellowstone. Within the advisory,
slick and snow-covered roads are expected, especially overnight
tonight into early Tuesday morning. In addition, weak instability
and a minor cap will result in the possibility of isolated, brief
thunderstorms over Southwest and Central MT late this morning
through early evening. Additional isolated thunderstorms are
possible for the western two-thirds of the CWA during the late
morning through afternoon hours of Tuesday. Lows will be near-
normal, while highs are expected to be about 5 to 10 degrees cooler
than normal for late April.
Jaszka

Tuesday night through Monday...An unsettled weather pattern will
continue to reside over the region into early next week. The
precipitation is likely to become more widespread by late
Wednesday through Friday. Total precipitation amounts for later
this week are still expected to average between 0.30 and 0.60
inches for many areas, with some isolated higher amounts. The main
concern will be during the overnight hours as snow levels lower
to around 3500/4000 feet or so. Thus some snow is possible in the
bigger cities at lower elevations later in the week. At this time
most snow accumulations at lower elevations will be on grassy
areas, but a few inches of snow are likely in the mountains each
day. Afternoon temperatures will be below normal through the
entire period, with Thursday/Friday being the coolest days.
Brusda

&&

.AVIATION...
Updated 0445Z.

VFR conditions are mostly expected through the day on Monday, but
MVFR conditions with possibly brief IFR conditions are possible with
showers. A few showers and thunderstorms may hold together through
08Z as they move southeast toward KLWT. Otherwise, another weak
disturbance will bring a good chance for additional rain/snow
showers through 12Z to Southwest Montana (KHLN KBZN KEKS). Yet
another disturbance will move into the destabilizing atmosphere
after 15Z Monday, bringing another round of showers/thunderstorms,
especially over Southwest Montana. Deep moisture will then combine
with a stationary frontal boundary and its upslope flow to bring
widespread MVFR/IFR conditions in rain/mountain snow after 00Z.
Coulston

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  54  33  50  33 /  30  40  60  40
CTB  51  32  47  32 /  60  70  80  40
HLN  54  36  55  36 /  40  40  50  40
BZN  51  34  52  32 /  50  60  50  50
WEY  40  28  43  26 /  70  70  50  40
DLN  49  35  52  33 /  50  70  50  20
HVR  56  33  47  32 /  30  30  60  40
LWT  52  31  43  31 /  40  50  60  50

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from noon today to noon MDT Tuesday
Gallatin.

&&

$$

weather.gov/greatfalls


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