Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 230927
Area Forecast Discussion
National Weather Service GLASGOW MT
327 AM MDT Sun Oct 23 2016
.SHORT TERM...for northeast Montana...today through Tue...
Cold high pressure moving across eastern Montana this morning. An
area of low cloud is over the far northeast corner of the state
with patchy fog along the edge. Otherwise mostly clear skies are
resulting in a cold and frosty morning for much of the region.
High slides into North Dakota today with low level flow going
around to the south. Upper ridge building over the state will
begin to pump warmer air northward. With flow becoming
increasingly downslope expect dry conditions with warming
temperatures from today through Tuesday. Ebert
.LONG TERM...Tue night through Sun...
The extended forecast period begins Tuesday evening with a
collapsing upper ridge, caused by a short-wave disturbance riding
along the upper flow through southern Saskatchewan. This is seen
in both the EC and the GFS. The disturbance might be far enough
north of Northeast Montana to not bring much in the way of
precipitation on Tuesday night or wind on Wednesday. But with a
weak cold front being sent into the local area, will go ahead and
increase overnight pops to slight chance and afternoon winds to
The upper ridge quickly rebounds Wednesday afternoon as the
short-wave moves into Manitoba. Limited moisture riding over the
ridge will meet the stationary frontal boundary over southern
Saskatchewan and areas north of the Hi-Line Wednesday night into
Thursday for the possibility of a few low qpf showers. However
confidence here is less due to the strength of the ridge depicted
by the EC.
Friday night into Saturday with timing more of an issue, another
short-wave rides across the ridge. Then ridging resumes for
Looking out a little further beyond the extended, Monday
afternoon and evening there looks like a cold front and short-wave
disturbance that could bring more rain showers and maybe wind.
Expect VFR, except for a slim chance for patchy MVFR/IFR fog in
the morning near the northeastern border with North Dakota.
Satellite IR imagery at 11u-3.9u shows low stratus over Sheridan
and East Roosevelt Counties, which is bringing IFR ceilings at
KISN this morning. This may possibly creep further south over
Models show an upper level ridge to our west that will bring in
dry and mild conditions for today.
Saturday rain showers added moisture, which might result in a few
areas of fog in the morning. Except possibly for KSDY, confidence
is not high enough to add to the TAFs. Will amend if needed.
Expect light west winds this morning. This afternoon wind will
shift to the east and increase to around 10kt.