885
FXUS65 KTFX 101114
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
520 AM MDT Fri May 10 2024

.SYNOPSIS...

Temperatures will warm to near normal today, and well above
normal over the weekend and into early next week. These above
normal temperatures will lead to snowmelt from the most recent
storm, which will lead to rising water levels on creeks and
streams over the coming days.

&&

.DISCUSSION...

Today through Sunday...A warm and relatively dry pattern is expected
as upper level ridging over the Pacific Northwest and Western Canada
is slowly suppressed through the period. Near normal high
temperatures today will climb well above normal over the weekend,
with temperatures peaking in the 70s on both Saturday and Sunday
despite falling heights aloft. A fast moving disturbance within
northwesterly flow aloft Saturday evening/night will bring a return
chance for shower and even a few thunderstorms to the plains of
Central and North Central Montana, with these shower and
thunderstorm chances lingering into the day on Sunday across
predominately eastern portions of Central and North Central Montana.

Monday through Tuesday...Ensemble clusters are in relatively good
agreement with a shortwave within initially zonal flow, and an
associated Pacific front, digging east/southwest and over/across the
Northern Rockies during the period. High temperatures ahead of the
shortwave and Pacific front on Monday will once again warm well
above normal and into the 70s, but fall back below normal and into
the 60s on Tuesday. Surface winds will be on the increase through
the morning hours on Monday ahead of the aforementioned Pacific
front, becoming breezy and gusty during the afternoon and evening
hours on Monday. While the latest NBM probabilistic data does not
support high winds materializing over this timeframe; most lower
elevations across Southwest through North Central Montana have
between a 20-50% chance of seeing wind gusts in excess of 35kts.
Light precipitation is also expected to accompany and follow the
passage of the Pacific front Monday afternoon/night, lingering into
the day on Tuesday as the upper level disturbance digs into the
Central Rockies. While widespread, heavy precipitation is not
expected over this timeframe, NBM probabilistic data does support
between a 40-70% chance for QPF amounts to reach or exceed 0.10"
across most of Southwest through North Central Montana.

Wednesday through next Friday...ensemble clusters diverge drastically
throughout the period, with the main difference between the clusters
being the timing of shortwave ridging and troughing. The multi-model
ensemble favors a more zonal pattern, with temperatures near normal
and daily chances for showers. - Moldan

&&

.AVIATION...
520 AM MDT Fri May 10 2024 (10/12Z TAF Period)

Expect clear skies and light winds across North Central and
Southwestern Montana today as high pressure continues to build into
the area. Some shallow ground fog may be possible through 15z, but
no impacts to airports are expected at this time. Ludwig

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

&&

.HYDROLOGY...

A Flood Warning remains in effect for Clear Creek in North Central
Montana through Saturday morning, with water levels expected to
slowly fall from minor flood stage to action stage over this
timeframe. Additionally, a Flood Watch remains in effect for the
nearby Bears Paw Mountains from this afternoon through the weekend
as warming temperatures and subsequent snowmelt runoff, and
remaining runoff from rainwater, could push creeks and streams out
of their banks.

Further south across the Island Ranges of Central Montana (i.e.
Highwood, Moccasin, Judith, Little Belt, and Snowy), increased
snowmelt and subsequent runoff into creeks and streams is expected
from Saturday through Monday as overnight temperatures and dewpoint
temperatures remain above freezing. This runoff could result in
waterways nearing bankful by Saturday night/Sunday morning; however,
confidence was not high enough at this time to issue a Flood Watch,
yet. None-the-less, those with interests along waterways prone to
flooding from rapid snowmelt should still be prepared to take action
should water levels begin to rise. - Moldan

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  68  42  76  43 /   0   0  10  10
CTB  74  45  77  45 /   0   0  10  10
HLN  71  41  78  47 /   0   0   0   0
BZN  64  33  73  40 /  10   0   0   0
WYS  62  27  66  30 /  10  10  10   0
DLN  66  36  74  40 /  10   0   0   0
HVR  72  46  77  48 /   0   0  10  30
LWT  62  38  70  41 /   0   0  10  10

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Watch from noon MDT today through Sunday morning for Bears
Paw Mountains and Southern Blaine.

&&

$$

http://www.weather.gov/greatfalls