Area Forecast Discussion
Issued by NWS Glasgow, MT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KGGW 191204
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
504 AM MST Fri Jan 19 2018

.DISCUSSION...
5 am update:

Given continuing light precipitation across southern and eastern
zones combined with ground temperatures hovering around freezing,
icy road conditions are still expected in some areas this morning.
As a result, the decision was made to extend the Winter Weather
Advisory through 15z. Travelers across the area should slow down
and allow a little extra time to reach their destination this
morning given these conditions in place. Maliawco

Previous Discussion:

A challenging forecast is at hand early this morning across
portions of northeast Montana. First, an area of light wintry mix
is tracking through the region. Radar echoes have now focused on
the southern and eastern portion of the CWA where a Winter Weather
Advisory remains in effect. While temperatures are above freezing
over much of the area, ground temperatures are around freezing in
many cases. As such, the wintry mix, light as it may be, may
still lead to some icy road conditions for a few places. It does
not take much ice to create problems, and so will let the advisory
ride for now.

The tricky part is that indications are that light precipitation
may continue for a time in the southeast zones even after 12z. By
about 15z, thermal profiles should be cold enough that any
lingering precipitation should be in the form of snow showers. The
question will be whether or not there is enough icing risk between
12z-15z to indicate an expansion of the advisory, or whether or
not to expire on schedule. Will assess trends and expected impacts
over the next couple of hours and arrive at a final decision.

The weekend ahead will feature a split trough moving over the
region with the colder air from the northern stream affecting
northeast Montana. That said, nothing like the recently
experienced Arctic conditions are expected. For added color, low
temperatures Saturday and Sunday night may reach the single
digits in some of the deeper river valleys with snow cover.

The next clipper system will approach from the west by Monday with
some increasing cloud cover, though with a lack of moisture do not
expect much precipitation with that at this time.

For the middle to second half of next week, the forecast was
trended toward latest consensus model blends with generally
seasonable or a little below average temperatures. Will be able to
better determine precipitation this period as model consensus
improves but chances may increase toward the end of the week wit
the next trough over the west. Maliawco

&&

.AVIATION...
VFR will prevail today. A light wintry mix early this morning may
lead to some icy conditions through 15Z at KSDY to KGDV.
Otherwise, expect any precipitation to end shortly after with dry
weather this afternoon into tonight. Winds will be west at 5 to 15
kts through the period. Maliawco

&&

.GLASGOW WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 8 AM MST this morning for Dawson...
Eastern Roosevelt...Garfield...McCone...Prairie...Richland...
Sheridan...Wibaux.

&&

$$

weather.gov/glasgow


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.