896
FXUS65 KTFX 091151
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
550 AM MDT Thu May 9 2024

UPDATED AVIATION SECTION

.SYNOPSIS...

Lingering shower activity will continue to diminish and end
heading into the afternoon hours. Much drier and milder conditions
are then expected for the weekend, but a passing disturbance will
bring some breeziness and a slight chance of a few showers and
perhaps a thunderstorm to the plains Saturday night into Sunday.
Additional weather disturbances are expected to pass through the
Northern Rockies early next week and bring unsettled conditions,
but temperatures look to remain at or above average.

&&

.DISCUSSION...

Abundant low level cloudiness, areas of showers, and even some
patchy fog can be found over North-central and Southwest Montana
this morning. Northeasterly flow aloft will more or less hang
around for one more day before the responsible low pressure system
weakens further and moves away from the region tonight. Scattered
showers are expected to be light and will diminish and end in a
northeast to southwest fashion as the day progresses. Temperatures
begin moderate from the chilly last couple of days, but will
still run slightly below average, especially over central and
southwestern locations where clouds will linger for much of the
day. No significant note worthies for tonight aside from some
patchy fog in spots with light winds and lingering moisture in
place amid partial clearing.

Ridging attempts to build in heading towards the weekend, but
there will still be a bit of a northwesterly flow aloft, leaving
an opportunity for a weak shortwave and cold front to pass through
the plains Saturday night into Sunday. This system will merely
bring some breeziness, a few clouds, and lower end shower and
isolated thunderstorm chances. The warming trend will generally be
uninterrupted with afternoon highs climbing well into the 70s by
Sunday.

Ensembles remain in fairly good agreement with another more
defined shortwave and cold front passing through Monday into
Tuesday, bringing more breeziness and scattered showers and
isolated thunderstorms to much of North-central and Southwest
Montana. Most suites favor a northwesterly flow aloft continuing
for the second half of next week, with about two thirds of them
favoring ridging to be more dominant and only a minority of
guidance leaning towards troughing and unsettled conditions. At
this time, there`s nothing really out of line from what`s normally
expected this time of year and temperatures look to run at least
near average even with the wetter model solutions. - RCG

&&

.AVIATION...
550 AM MDT Thu May 9 2024 (09/12Z TAF Period)

Overall, a high pressure ridge building into North Central, Central,
and Southwest Montana from the northwest will shift the decreasing
flow aloft more northeasterly, and surface high pressure will keep
winds fairly light through at least 10/12Z.

Details:

North-central Montana (KCTB, KHVR): VFR conditions will continue
through the period as mid-level cloudiness decreases from the north.

Central (KGTF, KHLN, KLWT) and Southwest (KBZN, KEKS, KWYS) Montana:
Mountain-obscuring low VFR/MVFR conditions with areas of fog and
scattered rain and mainly mountain snow showers will continue across
the area through at least 18Z, but IFR ceilings will linger at KLWT
until around 18Z. Clouds are expected to start lifting and breaking
up after then, with a chance of showers and MVFR conditions
lingering until 00Z along and south of a KEKS-KBZN-KLWT. Skies
should partially clear after 00Z, allowing patchy fog to form after
04Z. -Coulston

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

&&

.HYDROLOGY...

Much drier conditions move in for the upcoming weekend, with
limited opportunities for shower/thunder activity Sunday into
early next week; however, rivers, creeks, and streams originating
in the Bear`s Paw Mountains will continue to experience localized
rises. A Flood Warning remains in effect for the Clear Creek area
near Chinook through late Thursday evening.

Additionally, temperatures warming above average this weekend
will encourage melting snow over mountain tops and mid-slopes of
higher terrain in North-central and Southwest Montana for
increased water flow of out mountain tributaries. This may result
in potential minor ponding of water over adjacent low lying areas
and other locations normally susceptible to flooding. Those near
waterways and or flood prone areas should be alert to changing
conditions. - RCG

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  56  33  66  40 /  80   0   0   0
CTB  59  31  71  44 /   0   0   0   0
HLN  55  36  69  43 /  40   0   0   0
BZN  51  31  65  35 /  50  10   0   0
WYS  50  25  63  28 /  30  10   0   0
DLN  54  33  66  37 /  30   0   0   0
HVR  64  38  70  43 /  20   0   0   0
LWT  49  31  60  37 /  50  10   0   0

&&

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

$$

http://www.weather.gov/greatfalls