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058
FXUS65 KTFX 011750
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1150 AM MDT Sat Jun 1 2024

...AVIATION SECTION UPDATED...

.SYNOPSIS...

Expect warmer temperatures starting this afternoon and lasting
through the rest of the weekend into early next week. A weak
disturbance will bring the chance for showers and isolated
thunderstorms today and tomorrow to some areas. Starting Monday, a
stronger weather system will move through the area bringing more
widespread rain and gusty winds to the region. By Thursday, this
system is expected to move out, allowing for warmer and drier
conditions to settle by later in the week.

&&

.UPDATE...

Visible satellite imagery this morning continues to show mostly
sunny skies with a few cirrus clouds across North Central and
Southwest Montana. The current forecast is doing well for today
and no updates were made as high temperatures are still on track
to be in the 60s and 70s and a few rain showers/general
thunderstorms develops later this afternoon into the early
evening hours across Southwest Montana. Webb

&&

.AVIATION...

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01/18Z TAF Period

An area of scattered showers and a few isolated thunderstorms will
move through the region in a southwest to northeast fashion, mostly
between 02/00Z to 02/08Z. Lower VFR conditions and brief gusty winds
will be the primary concerns for this time period. Otherwise, expect
increasing mid- and higher level clouds this afternoon into tonight
and west to northwesterly breezes on Sunday in the wake of the
passing shortwave disturbance. - RCG

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.
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&&

.PREV DISCUSSION...
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/ISSUED 429 AM MDT Sat Jun 1 2024/

Saturday and Sunday... Generally quiet conditions will persist
through the weekend with some isolated showers and thunderstorms
possible Saturday afternoon through Sunday evening as a couple
weak shortwaves move across the region. Minimal accumulations are
expected except in isolated stronger showers. Highs this
afternoon will be around 10 degrees warmer than yesterday and put
temperatures slightly above normal for this time of the year. This
will kick off a trend of above normal temperatures that is
expected to last through all of next week.

Monday through Wednesday... The next impactful system will start
Monday afternoon as a surface low develops over southern Alberta
and a mid-level trough starts to dig in east of the Rocky
Mountains. Showers and thunderstorms will be possible Monday for
most locations along the Rocky Mountain front, central, and
southwestern Montana. During this time, winds will start picking
up, first along the Rocky Mountain front and then spreading
across north-central Montana overnight Monday into Tuesday
morning.

The strongest wind gusts are currently expected early Tuesday
morning through Tuesday afternoon. Ensemble guidance maintains
widespread probabilities of at least 60% for wind gusts over 58
mph for regions currently outlined in the high wind watch. Outside
the watch area, widespread gusts over 40 mph will be possible
for much of north-central and central Montana through Tuesday
evening. The main change with this forecast was winds did
increase along the Bears Paw Mountains and the hi-line east of
Havre. However, gusts are still well below criteria at this point
in time.

When looking at updated probabilities for gusts over 58 mph,
there is a trend over the last couple runs of the NBM that suggest
some of the higher wind gusts may last a little into early
Wednesday morning, mainly at higher elevations of the Rocky
Mountains. For now, given that this signal has only shown up in
the most recent model runs and with probabilities remaining under
50%, there is not enough confidence to extend or modify the
timing of the high wind watch. However, this will be something to
observe with future updates.

Thursday through Next Weekend... As the trough departs to the
east, an upper level ridge will build over the western CONUS
bringing above normal temperatures and drier conditions. For
Thursday through Saturday there is at least a 60% chance or
greater of hitting 80 degrees or higher across the lower
elevations of north-central, central, and southwestern Montana.
By Sunday the latest ensembles start to have some disagreement on
the placement of the ridge. However, the chances for above normal
temperatures are expected to continue into the following week
with CPC placing most of Montana in a slight (20%) risk of
excessive week through the second week of June.

-thor
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&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  75  48  72  54 /  10  20   0  20
CTB  70  44  68  50 /  10  10   0  20
HLN  77  50  74  55 /  10  30  10  10
BZN  75  46  72  51 /  10  30  30  10
WYS  67  41  64  44 /   0  30  30  10
DLN  74  44  71  52 /  10  20  10  10
HVR  75  50  75  53 /   0  20   0  10
LWT  72  45  69  50 /  10  40  10  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
High Wind Watch from Monday evening through Tuesday evening for
East Glacier Park Region-Eastern Glacier, Western Toole, and
Central Pondera-Northern High Plains-Southern High Plains-
Southern Rocky Mountain Front.

&&

$$

http://www.weather.gov/greatfalls