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fxus65 ktfx 231055 
afdtfx

Area forecast discussion
National Weather Service Great Falls Montana
455 am MDT sun Jul 23 2017

Aviation section updated

Synopsis...
expect another dry and warm day across the area today. Winds will be
gusty at times which will lead to an increased fire danger.
Thunderstorm chances return to start the week with the better chance
by midweek. Temperatures will remain slightly above-normal before
more hot weather returns by late week.

&&

Discussion...
today through Tuesday...an upper level ridge will begin to shift
eastward today...but hot afternoon temperatures are still
expected. A wind shift will move southward through the region
overnight, shifting winds to the north. On Monday, a brisk
westerly flow aloft develops resulting in very warm temperatures
by late afternoon. Temperatures remain near seasonal normals on
Tuesday as an upper level ridge begins to redevelop over the
Pacific northwest. There will be a small chance for a passing
wet/dry thunderstorm mostly on Monday and Tuesday over the eastern
and southern sections of the region. However, confidence is quite
low in any thunderstorm activity at this time. The main threat
from any storms will be the lack of rainfall and potential for
gusty winds. Brusda

Tuesday night through Sunday...latest model guidance continues to
illustrate a notable drying trend through the long range. Beginning
with Tuesday night and early Wednesday, a closed upper low rotating
off the northern coast of California will begin to get pulled slowly
northwards in response to weak ridging breaking down in SW Canada.
This shortwave will help feed increasing tropospheric moisture into
the area overnight with small, perhaps terrain enhanced nocturnal
clusters of showers and storms making its way as far north as SW
parts of the County Warning Area through daybreak Wednesday. It is looking like by
the daytime hours on Wednesday that most areas will remain dry as
the aforementioned weak ridge holds tight over the majority of the
area. However, by later in the afternoon and evening, increasing
spotty convection area wide will become a good bet, with a few
storms being strong given modest instability across central and
southern areas. Another important note will be lightning activity as
recent drought conditions may enhance the possibility of new fire
starts. Also, breezy conditions are looking possible Thursday
afternoon and evening with the passage of the shortwave trough that
may exacerbate fire weather conditions.

We begin to see a pattern shift beginning on Friday and lasting into
next weekend with the return of the dominant Four-Corners ridge in
the Desert Southwest. With good agreement on most long range model
guidance, i've started to bump temperatures up enough to reflect
this with highs easily reaching the lower to mid 90s area wide, with
perhaps upper 90's for some through next weekend. Of course this
will continue to be fine-tuned as we get closer in the week. Klg

&&

Aviation...
updated 1055z

Expect VFR conditions to continue areawide through the day today.
Some smoke from neighboring wildfires to the west might cause a
slight bit of a haze for areas mainly south of gtf to lwt, but
shouldn't cause a significant impact to visibility. Otherwise only a
few passing clouds possible. A quick moving front will dive south
from Canada overnight tonight across northern areas. Anticipate a
gradual wind shift for ctb and hvr roughly at or after midnight
tonight with gusty winds averaging 10 to 15 kt and gusts nearing 25
kt at times while remaining dry. Klg

&&

Fire weather...
red flag warning continues for today as gusty winds and low
humidity is expected this afternoon. A cold front will move
southward through the region during the overnight hours tonight.
Expect a wind shift to the north. The winds will be strong/gusty
at times overnight...especially over north central Montana. On Monday
expect breezy west winds to develop by the afternoon hours along
with low humidity. Thus a Fire Weather Watch has been issued for
this time frame. Additionally there is a small chance for a
passing dry thunderstorm. Some storms could produce strong gusty
erratic wind gusts. Brusda

&&

Preliminary point temps/pops...
gtf 95 57 87 51 / 0 0 0 0
ctb 91 51 79 46 / 0 0 0 0
hln 96 62 92 56 / 0 0 0 10
bzn 95 57 90 52 / 0 0 10 10
wey 85 48 82 46 / 0 0 10 10
dln 91 56 88 53 / 0 0 10 10
hvr 97 58 84 51 / 0 10 0 0
lwt 94 61 85 52 / 0 0 0 10

&&

Tfx watches/warnings/advisories...
red flag warning from noon today to 9 PM MDT this evening
central and eastern Lewis And Clark National Forest areas...
Chouteau and Fergus counties...eastern
Glacier/Toole/central/eastern Pondera/Liberty...Helena and
Townsend Ranger districts of the Helena National Forest...hill
and Blaine counties...Lewis And Clark National Forest Rocky
Mountain district-Rocky Mountain front...Lincoln Ranger district
of the Helena National Forest.

Fire Weather Watch from Monday afternoon through Monday evening
central and eastern Lewis And Clark National Forest areas...
Chouteau and Fergus counties...eastern
Glacier/Toole/central/eastern Pondera/Liberty...Helena and
Townsend Ranger districts of the Helena National Forest...hill
and Blaine counties...Lewis And Clark National Forest Rocky
Mountain district-Rocky Mountain front...Lincoln Ranger district
of the Helena National Forest.

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