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000
FXUS65 KMSO 201013
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
413 AM MDT Sun Apr 20 2014

.DISCUSSION...Instability showers and some gusty west/northwest
winds just behind a passing cold front will be scattered across
much of western Montana through mid morning. A ridge of high
pressure will quickly develop over the region this afternoon and
persist through much of Monday. Expect much warmer than normal
conditions on Monday with high temperatures potentially reaching
the lower to mid 70s.

Late Monday through midday Tuesday...Moist southwest flow ahead
of a major low pressure system will produce an increasing chance
of precipitation across the northern Rockies. There will be enough
instability in the atmosphere to bring a slight chance for thunder
with the scattered showers in southwest Montana and central Idaho.

Tuesday afternoon through Thursday...The major low pressure
system will cutoff and encompass the region. Temperatures will
lower to well below normal with widespread signifcant
precipitation expected. The following impacts are expected:

Glacier National Park region. Persistant rain/snow will wrap
around this low. This will increase the potential for rock/mudslides
and even avalanche concerns through Thursday. The Flathead valley
could even receive some light accumulation of snow on grassy
surfaces.

Potential for rock/mudslides along the highway 12 corridor in
Idaho county Tuesday afternoon through Wednesday morning.

Periods of heavy Snow over the mountains and mountain passes,
especially along the continental divide Tuesday night through
Thursday.

Significant rain creating Ponding of rain on roadways and some
rises on creeks and small streams in western Montana. Including
the Bitterroot, Missoula, Flathead, Mission Valleys as well as
southwest Montana.


A weak ridge once again moves over the region on Thursday
decreasing chances for precipitation. But the models are indicating
a fairly steady stream of showers moving through the region Friday
into the weekend.



&&

.AVIATION...Breezy conditions and a few showers behind a cold
frontal passage early this morning will impact all terminals
through mid morning Sunday. High pressure will strengthen this
afternoon and persist through Monday bringing vfr conditions to
all terminals.



&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$

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000
FXUS65 KMSO 192031
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
231 PM MDT Sat Apr 19 2014

.DISCUSSION...A weak disturbance is still anticipated to swing
through the Northern Rockies tonight into Sunday morning. This
feature will bring scattered showers to the region, but impacts
will be fairly minimal. A brief ridge builds back over the area by
Sunday evening which will last into Monday causing a period of
warming and drying.

Tuesday-Thursday...The warm weather on Monday will come to an end as
a modestly strong surface low pressure system embedded in a broad
trough swings through the Northern Rockies starting Tuesday
afternoon. The relatively warmer air-mass ahead of the initial
push of energy and moisture will have the potential to produce a
few thunderstorms across central Idaho and southwestern Montana.

One of the main impacted regions will be central Idaho.  Highway 12
in Idaho county could get a lot of rain in a very short period of
time with these showers and thunderstorms subsequently producing a
threat for rock and/or mudslides. Travelers and other personnel
should be extra vigilant Tuesday afternoon into the early morning
hours on Wednesday for the possibility of these hazards.

This system will quickly move to the northeast through western
Montana producing occasionally heavy rain in the valleys and a few
lightning strikes.  The rain could produce ponding on roadways and
create a slight rises to the smaller creeks and streams.  Some snow
could fall as low as the valley floor as the center moves over,
however snow isn`t anticipated to be much of an impact given the
presence of warm subsurface temperatures. However mountains and
mountain passes, especially along the Continental Divide, could see
periods of heavy snow from Wednesday morning into Thursday.

Models continue to indicate that the surface low pressure will cut
off from the main flow and sit just east of the continental divide
wrapping a lot of moisture into the Glacier Park region (including
Marias Pass). These locations are expected to be impacted the
greatest during this event due to the prolonged periods of rain
and snow. Snow could spread as far west as to Kalispell creating
slick conditions from Wednesday afternoon through the day Thursday.
Due to the heavy rain and snow rock and/or mudslides, as well as
avalanches could become an issue.

A weak ridge once again moves over the region on Thursday
decreasing chances for precipitation. But the models are indicating
a fairly steady stream of showers moving through the region Friday
into the weekend.

&&

.AVIATION...A weak disturbance will move through the region
tonight causing a steady lowering of clouds and scattered showers.
These showers will obscure mountains and passes at times. The
shower activity is anticipated to diminish by late Sunday morning
into the afternoon.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$

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000
FXUS65 KMSO 190954
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
354 AM MDT Sat Apr 19 2014

.DISCUSSION...A beautiful spring day will occur today with high
temperatures well into the 60s under sunny skies thanks to a high
pressure ridge over the area. Toward the end of the day a fast
moving weather disturbance will impact the region through Sunday
morning. Impacts from this system will be an increase in some
gusty winds with scattered showers across northwest Montana. This
will be short lived as:

Sunday and Monday will be under the influence of high pressure
again and bringing some pretty warm weather into the 70s on
Monday. This is about 10-15 degrees above normal.

Unfortunately the warmth and sun will go away as a large area of
low pressure establishes itself over the entire Tuesday through
Thursday. Southwest winds and instability will produce showers and
even a potential for thunderstorms Tuesday afternoon and evening.
Then things begin to crash Tuesday night through Thursday.
Temperatures will drop at least 20 degrees. Precipitation will
become likely across the entire NR with snow levels lowering to
near the valley floors. This system will finally leave the region
Thursday evening. Potential impacts from this system next week:

Significant snows over all mountain passes and higher elevations.
A mix of snow and rain in the valleys. Rock and mudslides are a
potential at the lower elevations.

Expect unsettled weather and temperatures below normal at the end
of next week.





&&

.AVIATION...Expect vfr conditions today at all terminals with an
increase in some mid to high level clouds after 20/0100z


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$

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000
FXUS65 KMSO 190331
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
931 PM MDT Fri Apr 18 2014

.DISCUSSION...An upper level wave moving through the region has
brought gusty winds near 40 mph across western Montana this
afternoon. Scattered rain and snow showers that are occurring now
will begin to taper off by this evening. There could be periodic
snow showers at Marias, Homestake and MacDonald Passes with a
chance for slush and reduced visibility. Wave heights up to 3 feet
have been observed by a NWS employee near Woods Bay while Flathead
Lake Biological Station weather sensors have measured sustained
winds near 30 mph with higher gusts. Expect winds to diminish
after sunset across western Montana.

A transient upper level ridge will move through on Saturday
providing for a chilly morning giving way to a pleasant day across
the Northern Rockies. High temperatures will rise into the 60s
which will be 5 to 7 degrees above normal for this time of the
year. There will be an approaching frontal system later in the
day and have added a slight chance for showers mainly over the
higher terrain across north-central Idaho Saturday afternoon, but
expect little precipitation.

Saturday Night...A quick moving weather system will offer a chance
of showers to northwest Montana and the Idaho Panhandle overnight.
Most areas will see increasing winds, especially higher terrain
across northwest Montana.

Sunday through Monday...A ridge of high pressure will be developing
over the Northern Rockies region Sunday, eventually moving into
eastern Montana by Monday. This will be a dry period with warming
temperatures. There may be increasing high clouds Monday for some
filtered sunshine.

Monday Night...A deepening low pressure trough will be approaching
from the west with gradually increasing clouds throughout the
night. In addition to clouds, a chance of rain is also in the mix
across Idaho and adjacent Montana zones by morning.

Tuesday-Thursday...Models continue to show a significant weather
system to impact the Northern Rockies beginning Tuesday afternoon.
There are some challenges to how strong the system will be and the
track of the low pressure and precip placement, but the following
discussion describes the best probability of occurrence.

After a nice day with partly sunny skies on Tuesday, the atmosphere
will become conducive for a few thunderstorms to develop ahead of
the main push of energy and moisture. The better locations for
thunderstorms will be central Idaho and extreme southwest Montana.
There is a lot of moisture associated with this system that could
put down very heavy rain in a short period of time. The potential
for rock and mudslides along highway 12 in Idaho and areas that
have experienced recent fire activity is a great concern into the
overnight hours on Tuesday and Wednesday morning.

The surface low pressure center will track northeast into western
Montana during the day Wednesday bringing much cooler temps and
rain, possibly mixed with snow at valley floors, especially
Wednesday morning. Moderate to heavy rain will likely create
widespread ponding and some rise to the smaller creeks and
streams. Mountains will likely see a heavy wet snow over the
mountain passes along the Continental Divide periodically creating
hazardous driving conditions. The low pressure will likely cut off
from the main upper level flow just east of Glacier National Park
wrapping moisture around the low into northwest Montana Wednesday
evening through Thursday. This region, including Marias Pass, will
likely be impacted the most with 12-24 hours of on and off snow.
Some snow could also spread even further west and impact lower
elevations such as West Glacier and the Kalispell area. Keep
apprised to possible forecast changes due to the complexity of
this system and the time we have until it occurs.

&&

.AVIATION...Wind and Scattered showers will be diminishing rather
quickly this evening as drier, more stable air moves in from the
west. An upper level ridge of high pressure will be building into
northern Idaho and western Montana during the next 24 hours. This
ridge will provide dry, more favorable conditions for aviation
operations. The only caveat to this pattern will be the potential
for patchy morning fog Saturday morning across the Idaho Panhandle
and northwest Montana, including KGPI.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$

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000
FXUS65 KMSO 182047
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
247 PM MDT Fri Apr 18 2014

.DISCUSSION...An upper level wave moving through the region has
brought gusty winds near 40 mph across western Montana this
afternoon. Scattered rain and snow showers that are occurring now
will begin to taper off by this evening. There could be periodic
snow showers at Marias, Homestake and MacDonald Passes with a
chance for slush and reduced visibility. Wave heights up to 3 feet
have been observed by a NWS employee near Woods Bay while Flathead
Lake Biological Station weather sensors have measured sustained
winds near 30 mph with higher gusts. Expect winds to diminish
after sunset across western Montana.

A transient upper level ridge will move through on Saturday
providing for a chilly morning giving way to a pleasant day across
the Northern Rockies. High temperatures will rise into the 60s
which will be 5 to 7 degrees above normal for this time of the
year. There will be an approaching frontal system later in the
day and have added a slight chance for showers mainly over the
higher terrain across north-central Idaho Saturday afternoon, but
expect little precipitation.

Saturday Night...A quick moving weather system will offer a chance
of showers to northwest Montana and the Idaho Panhandle overnight.
Most areas will see increasing winds, especially higher terrain
across northwest Montana.

Sunday through Monday...A ridge of high pressure will be developing
over the Northern Rockies region Sunday, eventually moving into
eastern Montana by Monday. This will be a dry period with warming
temperatures. There may be increasing high clouds Monday for some
filtered sunshine.

Monday Night...A deepening low pressure trough will be approaching
from the west with gradually increasing clouds throughout the
night. In addition to clouds, a chance of rain is also in the mix
across Idaho and adjacent Montana zones by morning.

Tuesday-Thursday...Models continue to show a significant weather
system to impact the Northern Rockies beginning Tuesday afternoon.
There are some challenges to how strong the system will be and the
track of the low pressure and precip placement, but the following
discussion describes the best probability of occurrence.

After a nice day with partly sunny skies on Tuesday, the atmosphere
will become conducive for a few thunderstorms to develop ahead of
the main push of energy and moisture. The better locations for
thunderstorms will be central Idaho and extreme southwest Montana.
There is a lot of moisture associated with this system that could
put down very heavy rain in a short period of time. The potential
for rock and mudslides along highway 12 in Idaho and areas that
have experienced recent fire activity is a great concern into the
overnight hours on Tuesday and Wednesday morning.

The surface low pressure center will track northeast into western
Montana during the day Wednesday bringing much cooler temps and
rain, possibly mixed with snow at valley floors, especially
Wednesday morning. Moderate to heavy rain will likely create
widespread ponding and some rise to the smaller creeks and
streams. Mountains will likely see a heavy wet snow over the
mountain passes along the Continental Divide periodically creating
hazardous driving conditions. The low pressure will likely cut off
from the main upper level flow just east of Glacier National Park
wrapping moisture around the low into northwest Montana Wednesday
evening through Thursday. This region, including Marias Pass, will
likely be impacted the most with 12-24 hours of on and off snow.
Some snow could also spread even further west and impact lower
elevations such as West Glacier and the Kalispell area. Keep
apprised to possible forecast changes due to the complexity of
this system and the time we have until it occurs.


&&

.AVIATION...Wind and Scattered showers will be diminishing rather
quickly this evening as drier, more stable air moves in from the
west. An upper level ridge of high pressure will be building into
northern Idaho and western Montana during the next 24 hours. This
ridge will provide dry, more favorable conditions for aviation
operations. The only caveat to this pattern will be the potential
for patchy morning fog Saturday morning across the Idaho Panhandle
and northwest Montana, including KGPI.


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...LAKE WIND ADVISORY until 9 PM MDT this evening Flathead/Mission
     Valleys.

ID...None.
&&

$$

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000
FXUS65 KMSO 181004
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
404 AM MDT Fri Apr 18 2014

.DISCUSSION...A cold front is passing through Idaho and western
Montana early this morning and will keep rain showers into this
morning. Conditions will dry out behind the front with the
exception being northwest Montana where showers will pass for much
of the day. Behind this cold front, gusty west winds will develop
today. Winds will increase through this morning and reach their
peak around mid-afternoon. Widespread wind gusts between 30-35 mph
can be expected though winds as high as 40 mph are possible. These
winds are going to make for choppy conditions on area lakes,
particularly Flathead Lake and Whitefish Lake where a lake wind
advisory is in effect.

Showers, cloud cover, and wind are going to decrease through this
evening as high pressure again takes hold of Idaho and western
Montana. Patchy fog remains in the forecast for early Saturday
morning, but wind this afternoon will likely cause fog to be very
isolated and of little impact. High temperatures are going to warm
nicely on Saturday but cloud cover will increase through the day
ahead of the next cold front. This cold front is on track to pass
late Saturday evening with gusty winds and rain showers to
associate. Temperatures will be a little cooler on Sunday with
general spring-time winds.

Warm temperatures will again return for Monday but the big story
is the high likelihood for a more robust weather system beginning
Tuesday. The predictability for a mid- week trough is quite high
which translates to high confidence in the weather system. Though
confidence is high for this trough to affect the region there are
important details that still need to be worked out. Some of these
details include, how much moisture will fall, how low will snow
levels drop to, will the trough and cold front quickly pass
through the region or will it develop into a slower moving/higher
impact system. At this time there are modest chances for moderate
rain ahead of the cold front followed by snow along the Continental
Divide. This upcoming weather system will continue to be closely
monitored and we will pass along additional information as details
become more clear.



&&

.AVIATION...A cold front continues to pass through the region this
morning with rain and and lowered ceilings common. Precipitation
will decrease though north central Idaho and western Montana this
morning and west winds will begin to increase. The main upper level
wave will move across northwest Montana today and help to initiate
rain and snow showers, some of which could help to bring down strong
gusty winds near 40 knots especially at KGPI, across Glacier
National Park south to KMSO between 18/1800z and 19/0000z. Terrain
obscurations will continue through today, although, terminals
KMSO, KBTM, and KSMN could see some improvement later in the day
with slightly drier air working in. High pressure will return for
tonight causing decreasing cloud cover.



&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...LAKE WIND ADVISORY from 11 AM this morning to 9 PM MDT this
     evening Flathead/Mission Valleys.

ID...None.
&&

$$

Kitsmiller

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000
FXUS65 KMSO 172055
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
255 PM MDT Thu Apr 17 2014

.DISCUSSION...Warm front precipitation mostly in the form of rain
is occurring across the region this afternoon and will continue
through this evening.

Tonight and Friday...A strong cold frontal system will be passing
through northern Idaho and western Montana tonight. This system
has a pretty good surge of Pacific moisture to go along with
strong dynamics. Rain and high mountain snow has already begun
across northwest Montana and northern Idaho and will spread across
the remainder of western Montana and north- central Idaho
overnight. Snow levels will be lowering after midnight with snow
eventually impacting the mountain passes along the Idaho/Montana
border, as well as the Continental Divide. Snow on the road
surfaces could make for some slick travel through the early
morning hours, but much of the snow is expected to melt thanks to
warmer road surfaces. Colder air will be ushered into the region
by strong westerly winds on Friday, following the passage of the
front. Winds will be increasing throughout the morning, then peak
during the afternoon hours with gusts up to 40 mph possible. In
addition to winds, the atmosphere will be quite unstable and
showers will be increasing in both coverage and intensity as we
enter into the afternoon hours. Wind and showers will make for
tricky conditions on area lakes and therefore a Lake Wind Advisory
has been issued for Flathead Lake and Whitefish Lake in northwest
Montana.

Friday Night and Saturday...A ridge of high pressure will begin to
build into the Northern Rockies region front the west on Friday
night. Showers and winds will be tapering off during the evening
hours as the atmosphere stabilizes and surface pressure pattern
relaxes. Drier, warmer conditions can be expected by Saturday as
the upper ridge migrates directly over the area. There could be
some patchy valley fog in the morning, if we see enough clearing
overnight.

Saturday-Monday...The ridge of high pressure will begin to break
down and move to the east late Saturday evening and overnight.
Winds will become fairly breezy Saturday night especially across
northwest Montana, north of Missoula. Wind gusts could approach
40 mph Saturday evening on Flathead Lake and surrounding
locations. This weak short wave system will keep showers and
clouds around much of western Montana keeping temperatures down to
normal values or slightly below Sunday. A weak and brief high
pressure will build over the region on Monday allowing things to
dry out and warm back into the 60s.

Tuesday-Thursday...Models continue to show a fairly strong/wet/cool
system moving across Idaho and over western Montana, then cutting
off and deepening across the Continental Divide late Tuesday into
Wednesday. The latest runs look more believable than the past few
runs. The GFS and ECMWF show a pronounced area of moderate to heavy
precipitation moving northeast from central Idaho through western
Montana into the the Glacier National Park area Tuesday night
through the day on Wednesday. Confidence is moderate for the
area of enhanced precipitation to develop, however the placement
of the precipitation is uncertain at this time. Operational
models are in disagreement on the track of the system. Though,
moderate to heavy valley rain and high mountain snow at times,
could become an impact. Mountain passes along the Continental
divide could see periods of Moderate to heavy snow creating
hazardous driving condition. The regions around Butte could even
see some snow, though at this time its tough to get a handle on
how much could fall. We haven`t seen anything like this for some
time, so this will need to be watched closely as we get closer to
the event occurring. As for forecast changes, made significant
changes for the chance of precipitation across the region, and
slightly dropped snow levels and temperature.


&&

.AVIATION...A very moist Pacific system will move through the
region tonight and Friday. Model soundings depict nearly saturated
below freezing layer between 5,000 and 12,000 feet MSL tonight
ahead and along the cold front posing some icing risks. Steady
rain ahead of a cold front will continue across the region through
this evening especially at KMSO and KGPI. The cold front is
expected to move through all the terminals between 18/0600 and
18/1200z. The upper level wave will move across northwest Montana
Friday and help to initiate rain & snow showers...some of which
could help to bring down strong gusty winds near 40 knots
especially at KGPI...across Glacier National Park south to KMSO
between 18/1800z and 19/0000z. Terrain obscurations will continue
through Friday...although terminals KMSO...KBTM and KSMN could see
some improvement later in the day with slightly drier air working
in.


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...LAKE WIND ADVISORY from 11 AM to 9 PM MDT Friday
     Flathead/Mission Valleys.

ID...None.
&&

$$

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