Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 251724 AAB
Area Forecast Discussion...UPDATED
National Weather Service GLASGOW MT
1124 AM MDT Tue Oct 25 2016
.SHORT TERM...for northeast Montana...today through Thu...
1116 am Update, The weak low pressure trough moving east
northeast across the area is producing very light sprinkles
or showers as it moves east from Valley and Garfield counties
this morning and will continue to produce some light precipitation
as it moves east into North Dakota.
953am Update, A weakening low pressure trough moving northeast
across a strong high pressure ridge will produce isolated to
scattered showers mainly across portions of Phillips and northern
Valley counties today. Updates were made this morning to add
shower chances in these areas. Showers chances were removed from
far northeast Montana.
Previous Short Term Discussion...
While a Pacific storm system rages west of Vancouver Island today,
Northeast Montana remains under a southwest flow aloft due to a
large ridge over the Central Plains. This pattern will bring
continued mostly dry conditions and seasonal temperatures. Weak
frontal boundaries might initiate an isolated shower or two, but
mainly expect partly to mostly cloudy skies.
Then tonight a short-wave trough swings across western Canada.
Although the disturbance will be too far north to effect Nemont
with any but isolated light showers, the wave will shift winds to
the west again.
Wednesday will see the return of the upper ridge for more
continued mild weather and seasonal temperatures. There will be a
frontal boundary orientated east-west across Nemont with cooler
air to the north. Overrunning moisture along this boundary will be
a focus for broken sky cover.
Thursday will see the ridge axis shift east. The movement of the
stationary boundary will also shift the sky cover east. Expect
continued pleasant conditions along with seasonal temperatures.
.LONG TERM...Thu night through Tue...
Upper ridge will move to the east Thursday Night and Friday. A
shortwave trough moving on the periphery of the ridge Thursday
Night could bring a slight chance of showers to the northwest part
of the forecast area.
Friday will start out dry with the area between waves. Then, the
next shortwave trough moves through Eastern Montana Friday Night.
This system has decent moisture with it along with an inverted
surface trough. Will maintain a chance of rain showers as
temperatures will be warm enough for all rain. A slight chance of
rain showers could linger into Saturday as models differ on how
quickly to move the system to the east.
Shortwave ridge should keep Saturday Night and Sunday dry. Then,
several waves are forecasted between Sunday Night and Tuesday as
models trend towards an upper trough with cooler temperatures over
the forecast area. Look for a chance of rain and/or snow showers
depending on temperatures. Forrester
There will be a mix low and mid level clouds across Northeast
Montana today with a few brief passing rain showers not expected
to impact the TAF sites much.
Flight Category: Mainly VFR expected with a few areas of MVFR
ceilings possible today.
Wind: E-SE wind 8 to 12 knots...becoming variable later this afternoon
and remaining light and variable tonight.