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000
FXUS65 KTFX 290601 RRA
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1201 AM MDT Thur Sep 29 2016

UPDATED AVIATION SECTION

.DISCUSSION...
Have made a minor adjustment to the Wx grid. Have added some patchy
fog to the Milk River area in Blaine County. Satellite imagery
indicating some low level moisture present there. Remainder of
forecast looks good. High pressure will keep skies clear overnight
with light winds. Increasing moisture over southwest Montana
tomorrow afternoon with isolated thunderstorms possible.

&&

.AVIATION...
Updated 0600Z.

Clear skies...light winds...and VFR conditions are expected for
tonight through Thursday morning. Some very patchy fog is possible
late tonight or early Thursday morning...however...confidence is too
low to place in TAF forecasts at this time. Mid level southwest flow
will increase moisture and mid level clouds for Thursday
afternoon...however VFR conditions will prevail through Thursday
evening. A few isolated thunderstorms will be possible Thursday
afternoon and evening...mainly across SW Montana...with some VCTS
possible near the KBZN area. Isolated thunderstorms activity will
then diminish shortly after sunset Thursday evening. Anglin

&&

.PREV DISCUSSION...ISSUED 338 PM MDT WED SEP 28 2016

Tonight through Friday...Fairly quiet weather will reside over the
region this evening...as an upper level ridge of high pressure
builds over the northern Plains. With mostly clear skies...another
cool but comfortable night is expected. On Thursday...a
southwesterly flow aloft will develop over the region. Weak upper
level disturbances will move from the southwest to the northeast
on Thursday...allowing for a few thunderstorms to develop. Most of
the storms will be south of a line from Helena to Bozeman...and
mostly during the late afternoon/early evening hours on Thursday.
For Friday...expect a few morning showers along the divide and
north of Highway 2...while another round of showers/thunderstorms
will be possible during the late afternoon over Central/Southwest
MT. The main concern from any thunderstorms on Thu/Fri will be
lightning for any outdoor events or activities. Afternoon
temperatures will be warm once again Thu/Fri...with temperatures
around 80 degrees at lower elevations. Brusda

Friday night through Wednesday...Dominant feature for the medium
range continues to be an upper level closed low that will start the
period along the British Columbia/Pacific Northwest coast. Models
agree that this system will move inland and transform into an open
trough over the western USA but continue to disagree on location,
strength and timing of the system as it affect Montana and the
Northern Rocky Mountain region. The models also continue to push
back timing of a surface cold front expected to move into the
forecast area over the weekend. As a result, forecast high
temperatures for Saturday and Sunday have climbed steadily higher
over the last few days. Period is expected to start off with
isolated/scattered showers and thunderstorms Friday evening through
Saturday evening with the best chance for precipitation expected
over the western and southwest mountains. As the upper system moves
inland the coverage of showers and stratiform rain/mountain snow
will expand across the entire forecast area for Sunday and Monday.
Tuesday and Wednesday will see a continuation of unsettled
conditions but have gone with only slight chance/chance PoPs due to
uncertainty of the upper low`s position. Temperatures for early to
mid-week will be much cooler with highs expected to be only in the
50s. mpj

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  45  76  49  81 /   0  10  10  10
CTB  41  72  45  76 /   0  10  10  20
HLN  44  79  46  80 /   0  10  10  10
BZN  43  80  48  80 /   0  10  10  10
WEY  32  65  39  70 /   0  20  20  20
DLN  43  77  45  76 /   0  20  20  20
HVR  45  76  48  79 /   0   0   0  10
LWT  45  81  51  79 /   0  10  20  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

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