416
FXUS65 KTFX 250617
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1217 AM MDT Tue Jun 25 2024

UPDATED AVIATION SECTION

.SYNOPSIS...

Isolated thunderstorms around Big Sky will diminish early this
evening, as windy and dry conditions prevail elsewhere over North
Central and Southwest MT. Expect dry and warm conditions on
Tuesday, but a return to scattered thunderstorms is expected on
Wednesday. The storms become more widespread on Thursday as cold
front moves through. Some storms could be strong Wednesday and
Thursday. Mountain snow returns to Glacier Park on Friday, with
light rain and cool temperatures over the rest of
North Central MT.

&&

.UPDATE...

A few showers are lingering in the mountains south of Bozeman
early this evening. These will subside over the next couple hours
as daytime heating wanes. Otherwise, a benign night is forecast.
No significant updates were needed this evening. -AM

&&

.AVIATION...
25/06Z TAF Period

VFR conditions are forecast to continue through at least 26/06Z
across North Central (KCTB, KHVR), Central (KLWT, KGTF, KHLN), and
Southwest (KBZN, KEKS, KWYS) Montana.

A moderate and dry westerly flow aloft will continue mostly clear
skies across the area with some mountain wave turbulence. As high
pressure aloft builds into the Pacific Northwest after 15Z, the
winds aloft and turbulence will decrease across the area. A more
northwesterly flow aloft will move a weak disturbance and associated
weak Canadian cold front southeast over the plains. The main impact
from this will be an overall shift to more northerly winds. It will
also bring scattered to broken mid-level cloudiness to the plains
between 18Z and 03Z. -Coulston

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

&&

.PREV DISCUSSION...
/ISSUED 500 PM MDT Mon Jun 24 2024/
Tonight through Tuesday...A weak upper level disturbance is moving
northeast between West Yellowstone and Big Sky. This disturbance
is producing a few thunderstorms. Most of these storms should exit
the CWA by early evening. Otherwise, dry and warm conditions will
generally prevail elsewhere over the CWA through Tuesday. Breezy
west winds will diminish this evening.

Wednesday and Thursday...A very warm day is expected on Wednesday,
with some lower elevation locations around 90 degrees. On
Wednesday afternoon, a stronger upper level disturbance will move
from southwest to northeast through the CWA. There will be enough
instability that a few stronger or an isolated severe storm is
possible. On Thursday, a cold front will move from west to east
across the CWA. The upper level flow will be divergent aloft,
resulting another round of thunderstorms over the CWA. There is
the potential for a few severe storms on Thursday as well, with
the best chances east of a line from Havre to Helena. Afternoon
temperatures will be the warmest over the eastern portions of the
CWA, as the cold front does not arrive until later in the day in
that region.

Friday through Monday...An upper level trof will move through the
northern portions of the CWA on Friday. This will be a rather cool
trof for this time of year, resulting in snow levels falling down
to about 7500 or 8000 feet over the northern Rockies, including
Glacier Park. Snow amounts will generally be low, in the 1 to 2
inch range for the highest peaks of Glacier. Light rain falls over
the remainder of North Central MT, with rainfall amounts of 0.15
to about 0.30 inches possible. Afternoon temperatures will be
about 8 to 12 degrees below normal on Friday. Temperatures rebound
a bit over the weekend, with the next chance for
showers/thunderstorms arriving around Monday. Brusda

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  48  80  53  89 /   0   0   0  10
CTB  45  75  50  83 /   0   0   0  10
HLN  53  88  57  91 /   0   0   0  20
BZN  49  87  52  84 /   0   0   0  30
WYS  42  81  44  78 /   0   0  10  30
DLN  48  87  51  83 /   0   0   0  20
HVR  49  80  53  87 /   0   0   0   0
LWT  48  76  51  83 /   0   0   0  10

&&

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

$$

http://www.weather.gov/greatfalls