Area Forecast Discussion
Issued by NWS Great Falls, 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 KTFX 192353
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
450 PM MST Sun Feb 19 2017

UPDATED AVIATION SECTION

.DISCUSSION...

Tonight through Monday...Skies are generally clearing across the
forecast area this afternoon with subsidence following the passage
of a shortwave trough. Scattered rain and mountain snow showers
linger over the forecast area but are expected to dissipate while
exiting to the northeast this evening. Additional new convection
is observed upstream over Idaho. Some of this activity could move
into the western and southwest mountains during the evening hours.
Subtle ridging aloft with weak warm advection maintains generally
fair and mild weather for Monday.

Monday night through Wednesday..Another atmospheric river sends a
surge a Pacific moisture into the region amid a strong southwest
flow aloft. Most of the accumulating rain and mountain snow will
remain along and west of the Continental Divide, though areas of
light precipitation are expected to move across central Montana at
times. A period of strong winds are expected Tuesday afternoon
across much of central, southwest and south-central Montana. This
is a somewhat atypical path for strong winds as the surface low
tracks through North-central MT with a lightning of the 700 hPa
gradient. If this feature arrives during the daytime, boundary
layer mixing will help bring these strong winds to the surface.
Temperatures trend cooler on Wednesday as this system weakens and
cooler air begins to move into the Pacific Northwest.

Wednesday night through Sunday...A northerly flow develops
bringing a return to more normal late-winter temps areawide. This
northerly flow will likely be accompanied by enough moisture for
periods of snow at times through next weekend.
PN

&&

.AVIATION...
Updated 2350Z.

VFR conditions are mostly expected through the next 24 hours.
However, the moist southwest flow aloft will continue mainly
mountain rain and snow showers. A disturbance in the flow will
continue to bring isolated to scattered showers (with the
possibility of a thunderstorm that could produce gusty winds) to the
Southwest Montana terminals through around 04Z. Clouds and showers
will generally decrease after 04Z as the disturbance exits the area.
Another surge of moisture will then bring a chance of showers to
Southwest Montana once again after 18Z.
Coulston

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  32  52  39  54 /  20  20  20  30
CTB  27  43  31  44 /  10  10  20  40
HLN  23  43  30  46 /  30  30  40  30
BZN  23  43  32  47 /  40  40  50  40
WEY  19  35  31  37 /  70  90  90  90
DLN  26  43  36  46 /  20  40  60  40
HVR  30  50  34  51 /  20  10  10  40
LWT  29  52  36  55 /  30  20  20  30

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

weather.gov/greatfalls


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