797
FXUS65 KTFX 202052
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
252 PM MDT Sat Jul 20 2024

.SYNOPSIS...

Scattered showers and thunderstorms will continue to drift across
North Central and Southwestern Montana through the remainder of
this afternoon and evening before dying down after sunset. Expect
the warmth to continue and build through mid week, with many lower
elevations areas seeing temperatures climb into the upper 90s to
low 100s for midweek. A cold front arrives on Thursday, bringing
gusty winds and thunderstorms before temperatures cool a few
degrees for the end of the week.

&&

.DISCUSSION...

Key Points:

-Warm to hot weather continues through Thursday with occasional
showers and thunderstorms

-Upper level ridge breakdown on Thursday will result in more
scattered showers and thunderstorms, along with increased wind
speeds, which may result in elevated to critical fire danger

Short term (through Wednesday)... Upper level ridging will
continue to remain parked over the Northern Rockies through the
first half of next week. With this ridge in place, temperatures
will remain warm through the weekend and early next week, before
the ridge amplifies ahead of an approaching trough. When this
ridge amplifies Tuesday and Wednesday, temperatures will warm
further to the upper 90s/low 100s across the lower elevations. As
far as precipitation goes over the next few days, expect most
areas to remain dry with just a few slow moving afternoon showers
and thunderstorms that pop up during the peak heating hours. While
the main threat from these showers and storms will be lightning,
isolated small hail or gusty winds cant be completely ruled out
given the dry air mass in place near the surface.

Extended (Wednesday through next Saturday)... Our upper level
ridge will face its first challenge this week as an upper level
trough approaching from the Pacific begins to intrude into its
turf over the Northern Rockies. As this trough facilitates the
collapse of the ridge over the Northern Rockies, expect winds to
become breezy across North Central and Southwestern Montana as a
cold front approaches, with showers and thunderstorms expected to
develop along and ahead of this front. While the storms themselves
could bring gusty winds in addition to the lightning threat, the
gusty winds behind the cold front that usher in the cooler air may
be the bigger concern, as they could help fan the flames of any
fires that manage to start from the thunderstorms. This system
will need to be watched closely by those with fire weather
interests.

Behind this system, broad upper level troughing will allow
temperatures to be a bit cooler than they have been, with most
areas seeing highs in the mid to upper 80s for most lower
elevation areas on Friday and Saturday, with just an outside
chance of a shower expected at this time. Ludwig

&&

.AVIATION...
20/18Z TAF Period

Note: The NWS Great Falls Weather Forecast Office manages the
following TAFs: KCTB, KHVR, KGTF, KLWT, KHLN, KBZN, KEKS and KWYS.

VFR Conditions continue for the duration of this TAF period. Density
altitude remains highly impactful to flight ops. Although conditions
remain VFR, haze/smoke from wildfires reduces visibility, at times,
and causes mountain obscuration. Isolated thunderstorms develop and
move across the region. Confidence is low in these storms entering
airfield 10-mile aerodromes. Aside from thunderstorm, winds,
generally, remain light, with gusts to 20KT, at times.
- Fogleman

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

&&

.FIRE WEATHER...

A ridge breakdown on Thursday may bring a round of widely
scattered showers and thunderstorms and gusty winds across the
area. Given the extended period of warm and dry weather preceding
this ridge breakdown, Thursday will need to be watched closely for
elevated to critical fire danger due to the storms and wind.
Ludwig

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  60  92  61  94 /   0   0   0   0
CTB  57  92  58  93 /   0   0   0   0
HLN  62  96  62  98 /   0   0   0   0
BZN  55  92  56  94 /  20   0   0   0
WYS  43  82  43  85 /  20   0   0  10
DLN  52  87  53  89 /  20   0   0  10
HVR  61  94  62  96 /   0   0   0   0
LWT  57  87  57  89 /  10  10   0   0

&&

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

$$

http://www.weather.gov/greatfalls