Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 302042
Area Forecast Discussion
National Weather Service GLASGOW MT
242 PM MDT FRI SEP 30 2016
.SHORT TERM...for northeast Montana...tonight through Sun...
Southwest flow aloft will prevail across the region ahead of a
deepening Pacific trough. This will maintain warm weather
conditions into the first half of the weekend with dry weather. A
shortwave embedded in the flow will allow for some showers and
potentially a thunderstorm late Saturday evening into Sunday.
The trough will translate east with the closed low centered over
Idaho stretching south into eastern Nevada by Monday. This will
bring considerably lower heights over the area and markedly cooler
temperatures. Highs in the 80s for Saturday will transition to
highs near 60 for Monday. Pacific moisture feeding into this
system will combine with dynamic lift to bring additional periods
of rain to northeast Montana as well starting Monday.
Given abundant rainfall potential starting late this weekend and
potential impact on travel with development of muddy road
conditions, etc., especially given recent steady rainfall, will
issue an HWO with this package as well to better highlight the
forecast concerns. Maliawco
.LONG TERM...Sun night through Fri...
12z models seemed to be fairly consistent with going forecast.
Thunderstorm threat did seem to be bit higher however Monday
afternoon given CAPES over 500 J/kg over the SE CWA.
Overall, impacts look to be minimal as far as Hydro concerns go
but, farmers who have yet to harvest their crop may see the
Latest models also showed cold air wrapping south into the area
Wednesday and Thursday that may lead to a mix with or a brief
period of snow. TFJ
A highly amplified and synoptically active weather pattern will be
common through the extended forecast period.
Beginning Sunday night and continuing through Thursday night, a
cold low pressure system from the Pacific Northwest and northern
Rockies regions will bring multiple periods of rain showers and a
few isolated thunderstorms to many portions of northeast Montana.
While precipitation amounts are still relatively uncertain, a
general 1 to 1.5 inches of rainfall can be expected for most locations.
A cold, north or northeast wind will prevail for most of the
forecast period. Temperatures will be coldest from around mid-
week through next weekend and although overnight lows will
approach near the freezing mark, do not expect rain to mix with
snow - at least not enough to include in the forecast with any
level of confidence at this time. The models are beginning to show
it in the central Montana higher elevations, but not for northeast
Mainly clear skies are expected through Saturday.
Winds will remain below 10 kts. TFJ