Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 150303

Area Forecast Discussion...Updated
National Weather Service Billings MT
903 PM MDT Sat Oct 14 2017

No significant changes to the forecast this evening.
Precipitation is no longer an issue as last of radar returns exit
the SE corner of Montana heading east. Main issue is the wind
threat in the western zones. Nye currently gusting to 48 mph and
just over 30 mph at Livingston. We have a wind advisory for the
gap locations (Livingston, Nye) which starts at 9 PM and goes to
noon tomorrow. Set-up for strong winds is not ideal due to
orientation of pressure gradient, which seems to favor a more
westerly component than south/southwesterly flow. However, the
case for strong winds does have support from MOS guidance, and the
forecast gradient tables we look at suggest a tighter gradient
after midnight. Not sure how that will happen as pressure falls
seemed to have peaked around Yellowstone County and are progged to
be sliding east in a few hours, but see no clear and hard reason
to mess with advisory highlight before it even becomes valid.
Midnight shift can monitor overnight.

We did slightly adjust overnight lows a bit, mainly going a
little lower in the eastern plains tonight than previously
thought. BT


.SHORT TERM...valid for Sun and Mon...

Upper level trough was quickly departing the region to the east.
Behind this trough, drier air, stronger mid-level flow, and
downslope flow off the western terrain has allowed conditions to
clear and warm through this afternoon. These warm temperatures
have also allowed us to tap into the stronger mid-level flow and
cause breezy conditions across the area this afternoon

Through the remainder of the afternoon and evening, the winds
will decrease over the plains around sunset. For foothill
locations like Livingston, Nye, Big Timber, and north towards
Harlowton, expect southwest winds to continue increasing through
the evening hours and overnight. We are expecting wind gusts from
50 to 60 mph overnight which will be hazardous to high profile
vehicles traveling through these cross-winds. Take special care if
traveling along routes such as Interstate 90, Highway 191, and
other local roads near the Beartooth/Crazy mountains. Have a plan
for alternate routes before the crosswinds develop. The strongest
wind gusts will begin to diminish Sunday morning as the pressure
gradient across these areas begins to relax, but conditions will
remain remain breezy across these areas through the duration of
the short term.

Expect warm and dry conditions through the remainder of the short
term as westerly flow aloft, combined with rising heights, keep
downslope conditions prevalent across the region. Kept
temperatures warmer than model guidance given the favorable
pattern for warm conditions. Expect temperatures to be in the mid
60s on Sunday and then likely hit the 70 degree mark on Monday.

.LONG TERM...valid for Tue...Wed...Thu...Fri...Sat...

Semi-zonal, anticyclonic upper flow should bring dry and mild
weather to the area Tuesday through Thursday. Strong winds are
possible again in the Livingston area Tuesday into Tuesday night
as surface pressures lower over northeast MT, enhancing the
pressure gradient over the southwestern CWA. Winds could gust to
50 mph in Livingston Tuesday night.

On Friday, an upper-level trough is progged to approach the
region. Large-scale lift ahead of the trough axis and a cold
front should produce some lower elevation rain showers and
mountain snow showers late Friday afternoon into Saturday. The
environment appears to favor only light rain amounts due to weak
large-scale ascent and westerly, downsloping winds.

High temperatures should generally be in the lower to middle 70s
Tuesday through Thursday, then drop to the 60s for Friday under
increased cloud cover. Northwesterly winds on Saturday should
bring in cooler air and decrease high temperatures to the 50s.


WSW surface winds will increase overnight at KLVM and in areas
adjacent to the foothills, with gusts of 40 to 50 kt. Gusts will
decrease late Sunday morning, then increase again Sunday evening.
VFR is expected across the area through Sunday evening. Arthur



    Sun     Mon     Tue     Wed     Thu     Fri     Sat
BIL 037/062 041/072 044/071 044/070 044/071 046/065 039/057
    00/U    00/N    00/U    00/B    00/U    11/B    32/W
LVM 037/062 038/071 039/070 041/069 040/069 042/059 035/052
    00/N    00/N    00/N    00/N    11/N    13/W    52/W
HDN 033/063 036/074 038/075 041/072 041/074 043/068 038/059
    00/U    00/U    00/U    00/B    00/U    01/B    33/W
MLS 031/059 037/073 040/074 043/069 042/072 042/068 039/058
    00/U    00/U    00/U    00/B    00/U    01/B    22/W
4BQ 032/059 035/072 039/074 041/071 040/071 043/069 038/058
    00/U    00/U    00/U    00/U    00/U    01/B    23/W
BHK 031/057 037/071 040/074 041/067 042/071 042/068 038/057
    00/N    00/U    00/U    00/U    00/U    01/B    11/B
SHR 029/060 034/070 037/074 039/071 039/072 041/066 035/055
    00/U    00/U    00/U    00/U    00/U    01/B    33/W


MT...Wind Advisory in effect until noon MDT Sunday FOR ZONES


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