... A major change to colder and unsettled weather through Sunday...
A much cooler air mass will work into the area tonight into much of
Friday. A major storm system may take shape Friday through Saturday
as a large low pressure system strengthens over the Great Basin
leading to the possibility of valley rain and mountain snowfall.
It will remain cool and unsettled in the northern mountains today
and Thursday with periods of light rain at the lowest elevations with
some occasional light snow in the mountains. Expect a cool
day east of The Divide on Thursday with a scattering of showers and
isolated afternoon thunderstorms across most of the area.
By Friday... the potential for a significant storm system may start
to affect areas east of The Divide. Areas of rain may
develop over the northern and central basins with wet snow in the
nearby foothills and mountains... especially from midday on. Some
light to locally moderate snow will continue in Yellowstone National
Park... the absarokas and bighorns. Some heavier snow is possible in
the northwest mountains Friday night and Saturday... especially The
Tetons northward into western Yellowstone Park in areas above 8000 to
8500 feet.
The storm system is then expected to gradually lift northward into
Montana Saturday night and Sunday. Cold Valley rain and mountain
snow will continue across the northern mountains... including
Yellowstone National Park through Saturday. Temperatures will start
to recover on Sunday in the northern mountains but it will still
remain quite unsettled in Yellowstone National Park on Sunday with
light valley rain and higher elevation snow showers.
Memorial Day looks much drier with more seasonable temperatures.
Travellers and those with outdoor plans should monitor the latest
forecasts from the National Weather Service on this expected major
change to colder and unsettled weather. Significant snowfall may
accumulate in the central and northern mountains during this
timeframe. The latest forecast can be found at
www.Weather.Gov/Riverton.
