074
FXUS65 KTFX 080200
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
800 PM MDT Fri Jun 7 2024

.SYNOPSIS...

A weak cold front will continue moving southward through
Southwest Montana through this evening, with a re-enforcing cold
front surging south across the entire Northern Rockies Saturday
afternoon and evening. These fronts will bring scattered clouds
and slightly cooler temperatures to the Northern Rockies through
Sunday. Mostly dry conditions will persist until late Sunday when
a passing weather disturbance brings a better chance for showers
and thunderstorms, with these chances for precipitation lasting
through Monday.

&&

.UPDATE...

No updates needed to current forecast for the overnight into
tomorrow period.

The loss of daytime heating has mostly caused clouds to dissipate
this evening across North Central, Central, and Southwest Montana.
The only exception to this is along the border with Idaho from
Monida Pass east to West Yellowstone. Isolated showers and
thunderstorms developed over the mountain peaks along the border
there around mid-afternoon, and they are continuing to generate
into this evening. However, the northwest flow aloft is keeping
the more active portions of the storms over Idaho. Regardless,
they should dissipate through midnight with further loss of
radiative heating from the mountain tops.

Otherwise, the gusty northerly winds from this afternoon have at
least become less gusty. These decreasing winds, along with mostly
clear skies and weak surface high pressure in place, should allow
temperatures to fall into the 40s tonight at lower elevations and
into the 30s in the mountains. The plains should warm into the 60s
tomorrow under the surface high, but the southwest valleys look to
warm into the 70s to lower 80s. -Coulston

&&

.AVIATION...

08/00Z TAF Period

A quiet pattern for the TAF period. VFR conditions prevail
through the TAF period. Isolated light rain showers along the
MT/ID border wind down this evening. Breezy surface winds from
the passing cold front in Southwest MT decreases this evening.
-Wilson

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

&&

.PREV DISCUSSION...
/ISSUED 540 PM MDT Fri Jun 7 2024/

Rest of today through Sunday morning...a cold front, which passed
through the plains of North Central and Central Montana this
morning, was beginning to move across the I-90 Corridor early this
afternoon. This front will continue to advance south towards the
Idaho border through the evening hours tonight and bring gusty
north through the remaining valleys of Southwest Montana thanks to
strong pressure rises further to the north as surface high
pressure slides south along the Canadian Rockies. Weakening cold
air advection into Central and Southwest Montana behind the
aforementioned front will help to mitigate the temperature change
from today`s highs through Saturday afternoon across the valleys
of Central and Southwest Montana; however, a re-enforcing cold
front surging south Saturday afternoon (plains of North Central
and Central Montana) through Saturday evening (valleys of Central
and Southwest Montana) will then bring the "coolest" temperatures
of the next week to all locations for the day on Sunday.
Predominately dry conditions are expected throughout the period,
but an inconsequential sprinkle or mountain shower can`t be ruled
out. - Moldan

Sunday afternoon through Monday... a passing shortwave begins to
exert an influence over the Northern Rockies, with scattered
shower and thunderstorm activity expanding in a southwest to
northeast fashion, peaking in coverage on Monday. Timing is not
very favorable for strong to severe storms at this time, but
forecast soundings for Monday do indicate that gusty winds may
accompany some storms with modest instability and inverted V
profiles, mostly over Central and Southwest MT.

Ensembles are in fairly good agreement with transient ridging
moving in on Tuesday and boosting temperatures to around 10 to 15
degrees above average before a more zonal sets up for the mid-
week period and cools things down closer to average and increases
winds. Aside from a few afternoon and evening
showers/thunderstorms, mostly dry conditions can be expected
through early Friday. There is some concern for low relative
humidity and gusty winds on Tuesday and Wednesday, although
grassland fuels still have some moisture to give for now. Most
ensemble suites highlight a Pacific trough bringing unsettled
conditions for next weekend, but there a significant
disagreements regarding position, timing, and depth. - RCG

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  43  68  43  66 /  10  10  10   0
CTB  43  63  39  63 /  10  10  10   0
HLN  48  79  49  73 /   0   0  10  20
BZN  45  78  47  72 /  10  10  10  20
WYS  41  76  43  73 /  10  10  10  50
DLN  45  81  45  75 /   0   0  10  40
HVR  47  68  41  64 /  10  10  10  10
LWT  44  68  42  65 /  10  10  10  10

&&

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

$$

http://www.weather.gov/greatfalls