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fxus65 kbyz 270245 
afdbyz

Area forecast discussion...updated
National Weather Service Billings Montana
845 PM MDT Fri may 26 2017

Update...
nothing to exciting going on over our region. Pacific moisture
caught in SW flow aloft from broad cyclonic circulation is
tracking over Wyoming. This is being limited in its northward
extent as northern stream short wave around the Hudson low moves
across NE Montana trying to phase with southerly stream. Bottom-
line, we are in-between forcing mechanisms with only some
northerly flow creating steep lapse rates over the area. This has
lead to some very isolated showers or sprinkles over the northern
third of County Warning Area while some showers from the south affect the big
horns region. This should all slowly come to an end with some
stabilization after dark and the southerly trough moving east.

We adjusted the pop's and cloud cover accordingly for this
evening. Forecast is in good shape. Broad cyclonic flow aloft will
result in some weak isolated to scattered showers again tomorrow
with surface heating. Bt

&&

Short term...valid for Sat and sun...

The short term continues to look unsettled, but nothing hazardous.
The low moving through Wyoming today will continue to move east,
skirting just south of the area tonight. The northeastern Bighorn
Mountains will see a few inches, but the track of the system will
favor the western and southern portions more. The area will
remain in northwesterly flow aloft through the weekend. There will
be enough moisture and instability lingering across the area from
Roundup, through Billings, to Sheridan and west could see afternoon
showers and isolated thunderstorms. The best chances will be over
the higher terrain. While there is some instability it does not
look enough to create any strong storms. With the rising heights
temperatures will return to normal tomorrow and continue to
gradually warm Sunday as the ridge axis moves closer. Reimer

Long term...valid for Mon...Tue...Wed...Thu...Fri...

Much of the long term will feature an upper ridge over the
northern rockies with northwesterly flow over the area. Weak waves
of energy will move down the east side of the ridge and through
the area producing showers and thunderstorms most afternoons and
evenings. Best chance for precipitation will be over the higher
terrain. By the middle to latter half of next week, models prog a
closed low to move onto the West Coast, eventually undercutting
the ridge and dropping south into the desert SW. Moisture and
energy is progged to rotate around the low and into the area
maintaining shower and thunderstorm chances. High temperatures
will gradually warm from the 70s on Monday, into the 80s by the
end of the week, increasing the snowmelt and causing flows in area
waterways to increase as well. Stp

&&

Aviation...

A few showers will affect the mountains and kshr area early this
evening, before dissipating overnight. Expect areas of mountain
obscuration, especially over the NE bighorns, otherwise VFR will
prevail over the area. Another chance of showers returns to the
area Saturday afternoon with a slight chance of thunderstorms.
Conditions will be mainly VFR, but MVFR is possible in any
heavier rainfall. Arthur

&&

Preliminary point temp/pops...

Sat sun Mon Tue Wed Thu Fri
-----------------------------------------------------------
bil 043/070 049/076 049/075 050/078 051/080 052/082 054/084
12/T 13/T 21/b 11/u 11/u 11/b 22/T
lvm 036/067 041/074 042/074 043/077 044/077 044/079 045/080
13/T 13/T 22/T 12/T 11/u 11/b 23/T
hdn 043/069 046/077 046/077 046/080 048/082 049/083 050/084
12/T 12/T 21/b 01/u 01/u 11/u 12/T
mls 044/072 048/076 045/075 045/078 048/080 050/082 053/083
11/b 11/u 00/u 00/u 00/u 01/u 11/b
4bq 043/068 046/074 044/073 043/076 047/079 048/080 051/081
12/T 11/b 10/u 00/u 00/u 12/T 22/T
bhk 041/068 044/071 041/069 039/073 043/074 045/076 048/077
11/b 11/u 00/u 00/u 00/u 01/u 11/b
shr 039/065 044/070 043/072 043/076 044/076 046/079 047/081
52/T 22/T 21/b 12/T 11/b 12/T 22/T

&&

Byz watches/warnings/advisories...
Montana...none.
Wyoming...none.

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