-- Discussion containing changed information from previous version are highlighted. --
923
FXUS65 KTFX 100554
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
838 PM MDT Thu May 9 2024

.UPDATE...

Satellite imagery this evening shows little or no clouds across
most of central and north-central MT as the west to east axis of
upper level ridging has sunk south to near the US/Canadian border
while some scattered to broken mid-level clouds continue to move
southwestward across mainly eastern portions of SW MT. Expect
clearing skies to expand south across remaining portions of SW MT
overnight as upper ridging and continues to shift southward with
surface high pressure also becoming centered across SW MT. Cannot
rule out patchy fog development for most of the area considering
recent moisture and dewpoints around 40F across much of the area
this evening beneath clear/clearing skies. Hi-resolution models
support the best chance for fog development in the Gallatin and
Madison river valleys as well as along the Missouri river in
Chouteau county and Milk River in Hill and Blaine counties.
Elsewhere, light but steady surface winds make the potential for
fog development less certain. The flood warning for Clear Creek in
Blaine county was extended with latest observations showing river
levels remaining steady near moderate flood stage this evening
and updated forecasts delaying the fall to below flood stage
until late Friday. Hoenisch

&&

.SYNOPSIS...
Expect clearing skies over the area this evening, as drier air
moves in from the west. Additionally, warmer air will gradually
move into North Central and Southwest MT starting tomorrow, with
the warming trend continuing through the weekend. There is a small
chance for showers in the Havre area on Saturday night, otherwise
it is looking like Monday is the next chance for a bit more
widespread shower or thunderstorm activity.

&&

.AVIATION...
-- Changed Discussion --
1155 PM MDT Thu May 9 2024 (10/06Z TAF Period)

Skies will continue to clear through the overnight hours tonight as
high pressure works in from the north. Given the recent rains, we
will have to watch for some patchy fog, but we should have enough
winds through the overnight hours to keep any fog development
limited, though KBZN and KEKS may have a better chance for fog
development, so I did include some BR in their TAFs. Otherwise, VFR
conditions are expected over the next 24 hours. Ludwig

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.
-- End Changed Discussion --

&&

.HYDROLOGY...
The flood warning will continue for Clear Creek. The water is
receding on the creek, but it will just take a bit more time before
the water levels go below flood stage.

The areal flood advisory has been replaced with a flood watch for
small streams and creeks that flow out of the Bears Paw Mountains
this weekend. In talking with emergency managers in this area this
morning, most creeks have receded from the recent rainfall. However,
warm temperatures are expected to develop on Friday and then
continue through the weekend. This could result in small streams and
creeks that flow out of the Bears Paw Mountains to come out of their
banks once again. Thus a flood watch has been issued for this area
for that potential.

Additionally, with warm temperatures expected elsewhere over the CWA
from Friday through Sunday, expect small streams and creeks that
flow out of the mountains of the remainder of North Central and
Southwest MT to begin to rise as well. Since many of these streams
and creeks are at lower levels, the threat/impact from any flooding
that could develop is lower at this time. Never the less, we will
continue to monitor the situation and should the potential for
flooding increase elsewhere over the CWA additional flood statements
might need to be issued over the weekend. Brusda

&&

.PREV DISCUSSION...
/ISSUED 555 PM MDT Thu May 9 2024/
Tonight through Sunday...An upper level ridge is trying to build
in from our west. This is resulting in drier air slowly moving
into the CWA. Thus most showers this afternoon will diminish by
early this evening, with clearing skies in many areas this
evening. Some patchy fog is possible by morning, especially over
North Central MT. Warmer air will move into the CWA each day from
Friday through Sunday, with Sunday looking to be the warmest day
for most. Generally dry conditions are expected Fri/Sat, but a
weak upper level disturbance will slide southeast from Canada into
the Havre area on Saturday night into Sunday. This disturbance
could produce a few light showers in the Havre/Harlem areas as the
disturbance moves through.

Monday through Wednesday...The weather pattern becomes a bit more
active early next week, with areas of surface low pressure moving
across southern Canada. This will result in scattered showers and
thunderstorms moving through the CWA at times for the first half
of next week. With the main area of low pressure to our north,
widespread heavy precipitation is not expected over the CWA at
this time. Afternoon temperatures will cool slight, but still
generally be above normal for most areas. Brusda

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  34  67  41  75 /   0   0   0   0
CTB  34  71  44  75 /   0   0   0   0
HLN  37  70  43  78 /   0   0   0   0
BZN  30  63  35  73 /  10   0   0   0
WYS  27  61  28  67 /  10   0   0   0
DLN  32  66  38  73 /   0   0   0   0
HVR  39  71  45  78 /   0   0   0   0
LWT  32  62  38  68 /   0   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Flood Watch from Friday afternoon through Sunday morning for
Bears Paw Mountains and Southern Blaine.

&&

$$

http://www.weather.gov/greatfalls