Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 310831
Area Forecast Discussion
National Weather Service GLASGOW MT
231 AM MDT TUE MAY 31 2016
.SHORT TERM...for northeast Montana...today through Thu...
Synoptic set up... a large area of hot high pressure exists over
the Desert Southwest and Four Corners with an upper ridge
extending north along the pacific Coast into British Columbia .
An upper low stacked with a surface low is currently over Eastern
Montana with the center of the low near Terry at 09z. Rain showers
are currently moving cyclonically across the north and west sides
of this low.
This low will move east into North Dakota this morning and bring
its back side showers east across the forecast area with it. This
will result in widespread rain showers for most of Northeast
Montana this morning. Tight surface gradient will allow for gusty
NW winds today. Will keep Lake Wind Advisory in effect for Fort
Peck Lake. This low will move far enough to the east this
afternoon that the showers will diminish across the western zones
this afternoon. It will be this evening before the showers
diminish in the east.
Surface high pressure moves into Eastern Montana tonight which
will diminish the winds and end the showers. Skies will also clear
from west to east tonight.
The upper ridge builds into Montana on Wednesday with dry weather
and warmer temperatures. Surface high will remain over the area
with light winds. The upper ridge remains over Montana Wednesday
Night with dry weather.
A shortwave trough will flatten the ridge on Thursday and frontal
system moves through the area in the afternoon. Look for a warm
day as thermal ridge will be over Eastern Montana. There will be
enough instability in the afternoon for a slight chance of
thunderstorms across the south. Forrester
.LONG TERM...Thu night through Tue...
Thursday evening zonal flow aloft over Northeast Montana will be
interrupted by a clipper moving across southern Saskatchewan.
There is limited moisture, so the cold front will likely produce
only a few light showers. Then by Friday morning flow aloft veers
to the northwest introducing more dry air. The main affect from
this system will be to produce gusty northwest winds Friday
afternoon, and to hold back the hot air from the building ridge in
The upper ridge builds over the western US and Canada starting on
Friday and strengthens over the weekend. Expect warm and dry
weather over the area. The ridge continues to build strength by
early next week. There is the possibility for the hot desert air
to nudge its way north into Montana for warmer temperatures than
the models are currently showing.
Spring storm continues to move east as it begins to stack up,
gaining more strength. The will increase northwest winds again to
around 20-30kt during the afternoon. Widespread rain showers will
affect the terminal areas with MVFR/IFR ceilings and visibilities
at times. Some dry air will be wrapped around the low center at
times for periods of VFR.
Most showers and the strong wind will move out of the area by
sunset this evening. High pressure moves into the region on
Wednesday for a return to VFR.
Lake Wind Advisory until 9 PM MDT this evening For Fort Peck
Lake for Central and Southeast Phillips...Central and Southern