Area Forecast Discussion
Issued by NWS Glasgow, MT
FXUS65 KGGW 241553
Area Forecast Discussion
National Weather Service GLASGOW MT
853 AM MST Fri Feb 24 2017
.SHORT TERM...for northeast Montana...today through Sun...
Going forecast was a bit heavy on the pops. Radar indicating
mainly flurries out there now. Another light surge of snow showers
are expected to move southeast across the area later
today/tonight, so higher pops for tonight look good. TFJ
Synoptic Setup: short term begins with a large pacific Airmass
running from the Great Plains through northeast montana and into
the Pacific Northwest. An embedded mesoscale trough/ridge/trough
setup is also in place respectively over these same locations.
the two trough pieces converge over an arctic airmass centered
over northern Saskatchewan. Farther upstream a second larger
ridge is nosing in from the Gulf of Alaska over northern British
Columbia and the Yukon Territory followed by and Alaskan Trough.
Today through Saturday: Meso-ridge will exit and PACNW meso trough
will move through the region during these periods. Limited CAA is
expected at the surface along with the current Pacific moisture
overriding this surface layer. This will keep low clouds intact
through most of the periods and continue to allow for scattered to
isolated seeder-feeder snow showers underneath at random.
Saturday night: Meso ridge from Yukon will move through leaving
partial clearing and dry conditions for roughly 12 hours.
Sunday: Alaskan Trough will arrive with a mix of pacific/arctic
air. Initially the Pacific moisture feed looks low but this could
increase rapidly into the evening and overnight hours. GAH
.LONG TERM...Sun night through Fri...
Upper trof over North America with northwest flow into Montana
will influence the weather pattern through most of next week.
Several shortwaves are expected to drop across the region
producing occasional light snow but no major event is anticipated.
Overall temperatures will return to near normal values for late
February for most of the period. Ebert
The amorphous upper flow has resulted in a high developing within
the middle of the broad upper level trough. This can be seen in
the clockwise rotation of the low stratus clouds and light
isolated snow shower radar echoes this morning.
Therefore, expect VFR/MVFR this morning. Conditions could
deteriorate this afternoon and evening as a weak frontal system
brings more light snow showers.
Winds 5-10kt from the southeast, veering to the north tonight.
Ice jams and high water levels continue at some of the sites.
The Milk River in Valley County stream levels have generally
stabilized. However, a flood watch continues mainly for the Milk
River, although the reading this morning at Glasgow brought the
river below action stage. The reading at Nashua has also stabilized
below action stage.
Ice break-up and ice jams are causing water levels to fluctuate
on the Yellowstone River near Glendive and further downstream,
although a report Thursday morning had the Yellowstone wide open
at Sidney. No flooding of concern has been reported. The Flood
Watch remains in effect for Dawson and Richland counties.
The water level on the Big Muddy River near Antelope crested at
11.35 feet or 0.65 feet below flood stage and is now slowly
falling. Plugged culverts in the area appear to have been
cleared. A Flood Watch remains in effect here.
Some county controlled low water crossings over the area do have
water running across them.
The Frenchman Creek in northeast Phillips county has crested at
13.45 feet and dropped below 10 feet of action stage. The Flood
Warning was cancelled Thursday night for this creek system.
Cool temperatures have slowed down melting.
Flood Watch until 4 PM MST this afternoon for Central and