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000 
FXUS65 KTFX 201045
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
444 AM MDT Sun Aug 20 2017

UPDATED AVIATION

.SYNOPSIS...

West to northwest flow aloft will continue over the region through 
Monday. Precipitation is not expected, but areas of wildfire smoke 
will persist. Near-normal temperatures are forecast through Monday. 
Tuesday and Wednesday will feature above-normal temperatures as high 
pressure aloft builds-in from the Pacific Northwest. Fair weather 
will likely persist through mid-week. 

&&

.DISCUSSION...

Today through Tuesday...Several weather disturbances embedded in 
westerly to northwesterly flow aloft will cross our region through 
Monday morning. However, these disturbances should encounter limited 
moisture and very little, if any instability. Thus, the main affects 
should be passing mid- to upper-level cloud cover. Decreasing cloud 
cover from west to east and dry conditions are still expected for 
Monday's solar eclipse. A high pressure ridge aloft will then build-
in from the Pacific Northwest later Monday through Tuesday, allowing 
fair weather to persist. Near-normal temperatures are in the cards 
today through Monday night. On Tuesday, highs will be roughly 5-10 
degrees above-normal as the aforementioned ridge and associated 
warmer air build over the area. 

Tuesday Night through Sunday...Aforementioned high pressure ridge 
aloft will continue to traverse the CWA from west to east Tuesday 
night through Wednesday, allowing warming temperatures and primarily 
dry weather to persist. Somewhat cooler temperatures, along with 
scattered showers and thunderstorms, remain possible on Thursday and 
Friday due to an upper-level trough digging southward and eastward 
from British Columbia. In addition, a Pacific cold front 
accompanying this trough should sweep eastward over the CWA on 
Thursday. Drier conditions and slightly warmer temperatures should 
return next weekend, as another high pressure ridge aloft builds-in 
from the south and west. Near to slightly above-normal low 
temperatures are expected throughout the period. High temperatures 
are forecast to be about 10 degrees above-normal Wednesday, while 
highs Thursday through next weekend should be near or slightly above-
normal. Friday should be the coolest day as our region resides 
within a post-frontal environment and beneath the aforementioned 
trough aloft.
Jaszka 

&&

.AVIATION...
Updated 1044Z.

Westerly to northwesterly flow aloft and mainly VFR will persist 
next 24-hours. Several disturbances embedded within the flow will 
likely be accompanied by nothing more than periods of mid- to upper-
level cloudiness. Areas of wildfire smoke and distant mountain 
obscuration remain possible, especially over Central and SW MT. 
Smoke may reduce VSBY to MVFR at times, but confidence is low.
Jaszka  

&&

.FIRE WEATHER...

Fire weather highlights are not anticipated through mid-week, but
cannot be totally ruled-out due to continued warm, dry, and 
potentially breezy conditions. Fire weather concerns should 
increase on Thursday, when the upper-level ridge collapses over 
Montana and a surface cold front spreads gusty winds and 
scattered thunderstorms, some dry, over the area. 
MPJ/Jaszka

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  81  49  81  52 /   0   0   0   0 
CTB  78  44  78  47 /   0  10   0   0 
HLN  81  52  85  53 /   0   0   0   0 
BZN  81  47  84  49 /   0   0   0   0 
WEY  75  37  77  36 /   0   0   0   0 
DLN  79  46  82  48 /   0   0   0   0 
HVR  82  48  81  51 /   0   0   0   0 
LWT  79  49  80  50 /   0  10   0   0 

&&

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

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