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Area forecast discussion 
National Weather Service Great Falls Montana
540 PM MDT Fri Mar 27 2015

Updated aviation section

tonight through Sunday...the main weather feature during the
period continues to be an upper trough which is forecast to move
into western Montana Saturday morning and be in eastern Montana by
Saturday evening. Associated with the upper trough will be a cold
front which will move through the forecast area Saturday morning.
Precipitation will develop over the mountains of the Rocky
Mountain front by Saturday morning then continue into Sunday
evening. Snow levels near 9000 feet ahead of the front will fall
to as low as 5000 feet during the afternoon. Mountains of the
Rocky Mountain front will see several inches of snow with amounts
up to 6 inches possible. Scattered showers and gusty westerly
winds will occur over the plains and southwest valleys Saturday
afternoon as the trough moves into the area. Models are indicating
some better lift near the U.S. Route 2 area so have gone with
showers likely for this particular area. Expect showers in the
east to linger into the evening and have increased the chances of
precipitation from the previous forecast. Late Saturday night into
Sunday the forecast area will be under the influence of a broad
upper ridge over the northwest U.S. Expect dry weather with the
possible exception of the Rocky Mountain front where there could
be a few rain or snow showers. There will be gusty westerly winds
Sunday but they will not be as strong as those of Saturday.

High winds...confidence is high for the Rocky Mountain front that
the high wind watch has been upgraded to a high warning. Elsewhere
confidence is marginal for a high wind event so will continue to
ride with the current high wind watch. Blank

Sunday night through Friday...broad high pressure will extend across
the Great Basin and northern rockies from Sunday night through tues
morning, making for quiet weather conditions with high temperatures
in the upper 60s to low 70s on Mon. The first element of a trend
back toward more seasonal conditions is forecast to occur on tues as
a quick-moving shortwave trof and surface cold front cross The
Divide by late morning. Forecast models have been consistent for
several runs in showing scattered areas of light valley rain/mtn
snow on tues aftn/eve, with slightly better chances of precip over
southwest Montana. Also, still keeping an eye on tues for possible high
wind highlights for the central and hiline counties as projected
winds aloft and surface pressure gradient remain favorable for gusts
of 50 mph or more. The remainder of the week is basically an
unsettled pattern with persistent northwest flow aloft. A couple of
additional shortwaves will move through the flow on thurs and late
Fri, bringing periods of scattered rain/snow showers. The region's
current run of well-above normal temperatures will end with the
weather system on tues as daily highs will trend downward into the
low-mid 50s for Wed through Fri.


updated 2340z.
High pressure aloft will continue to provide dry and stable
conditions. A disturbance aloft and an associated cold front will
move across the area after 15z with winds becoming gusty along and
behind the front. Showers will also develop behind the front. VFR
conditions prevail with increasing MVFR conditions due to low
ceilings and precipitation after 18z. Mountains will become obscured
at times.


Preliminary point temps/pops...
gtf 46 60 37 63 / 0 30 20 0
ctb 45 56 37 60 / 10 60 10 0
hln 43 60 36 63 / 10 20 10 0
bzn 37 63 29 63 / 0 30 10 0
wey 33 55 22 53 / 10 40 20 0
dln 42 60 31 61 / 0 30 0 10
hvr 41 63 33 67 / 0 60 30 0
lwt 47 62 35 63 / 0 50 30 0


Tfx watches/warnings/advisories...
high wind watch from Saturday morning through Saturday evening
Blaine...Cascade...central and southern Lewis And Clark...
Chouteau...eastern Glacier...eastern Pondera...eastern Teton...
Fergus...hill...Judith Basin...Liberty...Meagher...Toole.

High Wind Warning from 3 am to 9 PM MDT Saturday northern Rocky
Mountain front...southern Rocky Mountain front.




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