Area Forecast Discussion
Issued by NWS Glasgow, MT

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FXUS65 KGGW 191509 AAA

Area Forecast Discussion...UPDATED
National Weather Service Glasgow MT
909 AM MDT Thu Oct 19 2017

.SHORT TERM...for northeast through Fri...

A mild day is expected with highs reaching 20F degrees above
normal. There will be mid-to-high clouds as the trough off the
West Coast feeds moisture into the upper flow. The main concern
today will be fire wx with the expected low RHs. There is a
surface trough spreading east through the prairie provinces that
may energize the wind somewhat - to around 10-15kt - generating
enhanced fire wx conditions. Updated near term wind grids, along
with sky cover to match conditions. Otherwise, with mild
conditions and no precipitation, few other grid edits were


Previous discussion -
As the upper-level trough quickly exits the region toward the
east, an intermediate, short-wave ridge of high pressure takes
its place today, providing our area with very warm and dry
conditions now through Friday.

True, humidity levels will drop today into the teens, but winds
are expected to increase into the teens at most, creating marginal
fire weather concerns at worst. At this time, we do not see the
for any fire weather headline products, but the situation bears
keeping an eye on today.

By Friday afternoon, a significant change in the weather pattern
begins to form. What has been a generally zonal flow over the
region starts to change to more of an amplified pattern leading
into the weekend, bringing increased chances for rain showers.


.LONG TERM...Fri night through Thu...

Friday evening through Saturday morning, models are indicating
that the best chance for rain showers will be focused along the
position of the cold front as it moves from west to east across NE
Montana. At this time, the NAM is showing more rainfall than the
other models concentrated between highways 24 and 191 - more than
0.25 inch. The other models show a more widespread area of lesser

Later on Saturday, a few lingering rain showers are possible as
the main trough axis and closed low finally sweeps the last of
that moisture through the area.

Sunday through Tuesday morning, a sudden low pressure drop will
drop into the region from the Canadian Rockies, bringing another
round of some scattered rain showers. Models here show a bit more
disagreement. Tried to advertize the best consensus I could find.

Tuesday afternoon and beyond, the upper-level trough continues to
push east and south, while the next ridge of high pressure builds
into our region from the west with the usual amount of model
discrepancy this far out in the forecast.





SYNOPSIS: Strong high pressure building into the region will act
to clear out the skies to mostly sunny today, with the flow aloft
turning more out of the SW by the end of this TAF cycle.

WIND: Variable winds around 10 kts this morning will set up from
the southwest today 10-15 kts, then from the south later this
afternoon, then becoming light and variable again late tonight.




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