Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 230901
Area Forecast Discussion
National Weather Service GLASGOW MT
301 AM MDT Sun Apr 23 2017
.SHORT TERM...for northeast Montana...today through Tue...
A cold front has moved to the south and west of the forecast area
this morning. The frontal boundary will be quasi-stationary over
Central Montana today with a low pressure system over Wyoming. A
tight pressure gradient between the low and high pressure over
Manitoba will allow for gusty east winds over parts of Northeast
Montana today. Will keep Lake Wind Advisory in effect for Fort
Peck Lake. WSW flow aloft will allow for some light overrunning
moisture which could bring isolated to scattered rain showers
(mixed with snow in the NE corner this morning) to parts of the
A shortwave will break away from a Pacific NW upper low today. This
trough and move across Eastern Montana this afternoon and tonight.
Moisture will continue to overrun the stalled frontal boundary
over Central Montana and bring precipitation to the forecast area.
Temperatures will be below freezing late tonight in some areas
along and north of the Missouri River which will allow rain to
change to snow. At this point, it looks like there will be up to an
inch of snow in this area.
While this wave moves to the east Monday morning, additional
shortwaves are expected on Monday with slow moving frontal
boundary either over the forecast area or just southwest of it.
Will maintain a chance of light rain or snow in areas where
temperatures will be near freezing.
Upper trough moves into Montana Monday Night and Tuesday allowing
for somewhat colder temperatures. Waves within the trough will
keep chances for rain and/or snow showers going over most of the
forecast area. Forrester
.LONG TERM...Tue night through Sun...
The extended forecast period will be dominated by a large low-
pressure trough pattern aloft as repeated large weather
disturbances dive toward the south and southeast from the Rocky
Mountains through the high/central plains regions.
While this will likely result in weather conditions more active
and interesting elsewhere, NE Montana will reside in the colder
air influence of this pattern. Cold enough, in fact, to introduce
a chance for rain changing to snow each night if precipitation is
in the area. This seems most likely from Wednesday morning through
Thursday with what seems like a back-door cold frontal system from
Saskatchewan. Models are generally presenting this precip as
scattered and somewhat disorganized, but tried to adjust the
forecast to line up with the best model consensus I could find.
May result in a few periods of light accumulations of snow across
our northern zones.
Thursday night through the weekend, a large and powerful low
pressure system digs even further south through the central and
southern Rockies and will probably set the stage for some severe
thunderstorms over the central plains region by Friday afternoon.
Again, NE Montana is completely removed from any of these severe
weather dynamics to be of any concern. Just dealing with a
repeated cold and unsettled weather patterns locally.
SYNOPSIS: With NE Montana TAF sites located on the cold side of a
quasi-stationary front, persistent low level clouds have settled
in over the region. A few hit and miss scattered rain showers are
possible, but not confident enough to include it more than just a
mention of vicinity showers for now.
Flight Conditions: MVFR to borderline IFR.
CIGS: Generally 1000 to 2000 feet.
WIND: From the east at about 20 kts.
Lake Wind Advisory until 6 PM MDT this evening For Fort Peck
Lake for Central and Southeast Phillips...Central and Southern