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990
FXUS65 KTFX 051027
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
427 AM MDT Wed Jun 5 2024

.SYNOPSIS...

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Winds will gradually decrease today with warmer and drier
conditions following through the rest of the week with just a few
showers and thunderstorms across Southwestern Montana during the
afternoon.
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.DISCUSSION...

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Today... Based on recent observations, the surface winds have de-
coupled from the stronger flow aloft which has led to much lower
surface wind speeds than what was originally forecasted. When
looking at the latest model guidance there is about a 50/50 split
as to whether the stronger winds aloft will be able to mix back
down to the surface again. Should models like the HRRR pan out,
portions of central Montana may still catch a gust up to 60 mph
this morning. But should things lean more towards the RAP, then we
might be well past the peak wind for this event. Given that enough
of the models are still pointing towards a high wind threat this
morning, I elected to let the high wind warning run its course
through noon today.

Otherwise, light showers will be possible this morning along the
Rocky Mountain Front and the hi-line. These showers will taper off
by the early afternoon leaving warm and dry conditions for the
rest of the day.

Thursday thru Saturday... An upper level ridge will build over
the western CONUS leading to much warmer temperatures with lower
elevations seeing highs in the mid 70s to low 80s and higher
elevations ranging from the low 60s to the low 70s. Dry conditions
will persist across north-central and central Montana with a
chance for scattered afternoon thunderstorms in southwestern
Montana through the weekend.

Sunday thru Monday... A weak disturbance will move across the
state bringing a more widespread chance for showers and afternoon
thunderstorms. Showers are generally expected to be light,
however, some ensemble members are starting to point towards a
chance for heavier precipitation in southwestern Montana. That
being said, specific details are far from resolved at this point
in time.

Early Next Week... Long-range model guidance shows the ridge axis
moving further east around Monday and remaining more aligned over
Montana through early next week. As such, temperatures in the
extended forecast are showing the potential to be even warmer with
more widespread temperatures above 80 degrees possible. Specifics
are still to be determined as some disagreement in the exact
placement of the ridge axis remains. But it might finally be safe
to say that summer is here... and here to stay.

-thor
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&&

.AVIATION...

05/06Z TAF Period

VFR conditions prevail through the period with some broken mid level
clouds across primarily southwest MT overnight and few isolated
showers near the continental divide before any lingering cloud-cover
diminishes Wednesday morning. Strongest mid-level westerly flow is
passing across the region tonight with associated mountain wave
turbulence persisting through the overnight period before gradually
decreasing on Wednesday. Surface winds have de-coupled from the
stronger flow aloft at many TAF sites, resulting in decreased wind
speeds but periodic gusts of 30-40kts are possible at most north-
central MT TAF sites with low-level wind shear common at all sites
through 15z Wednesday. Winds aloft and at the surface gradually
decrease Wednesday afternoon/evening. Hoenisch

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

&&

.PRELIMINARY POINT TEMPS/POPS...
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GTF  71  42  81  48 /   0   0   0   0
CTB  67  39  76  44 /   0   0   0   0
HLN  76  47  86  54 /   0   0   0   0
BZN  76  44  84  51 /   0   0   0   0
WYS  72  40  77  45 /   0   0   0  10
DLN  76  45  84  51 /   0   0   0   0
HVR  71  44  77  48 /   0   0   0   0
LWT  66  42  75  46 /   0   0   0   0
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&&

.TFX WATCHES/WARNINGS/ADVISORIES...
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High Wind Warning until noon MDT today for Bears Paw Mountains
and Southern Blaine-Big Belt, Bridger and Castle Mountains-
Cascade County below 5000ft-East Glacier Park Region-Eastern
Glacier, Western Toole, and Central Pondera-Eastern Pondera and
Eastern Teton-Eastern Toole and Liberty-Fergus County below
4500ft-Hill County-Judith Basin County and Judith Gap-Little
Belt and Highwood Mountains-Meagher County Valleys-Northern
Blaine County-Northern High Plains-Snowy and Judith Mountains-
Southern High Plains-Southern Rocky Mountain Front-Upper
Blackfoot and MacDonald Pass-Western and Central Chouteau County.
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&&

$$

http://www.weather.gov/greatfalls