Area Forecast Discussion
Issued by NWS Great Falls, MT

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FXUS65 KTFX 251523
AFDTFX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
923 AM MDT Fri Jul 25 2014

.UPDATE...

No significant changes made to forecast with High Wind and Red Flag
Warnings remaining in effect. Increased winds from this
morning through the afternoon across most of north-central Montana.
GTF already has had gusts over 40 mph this morning. The large low
pressure center over the Alberta/Saskatchewan border will continue to
slowly move eastward through the day. Strong 700-650 mb winds of ~40
kts on the southern periphery of the low`s circulation will lead to
widespread gusts over 40 mph...with gusts over 55 mph likely in the
favored downsloping areas east of the Rocky Mountain Front. The
gusty winds should drop off rapidly after 7 or 8 PM as diurnal
mixing wanes. Uttech

&&

.AVIATION...
UPDATED 1135Z.
Skies will remain mostly clear with widespread VFR conditions
through Saturday morning. Strong and gusty westerly winds along the
east slopes of the Rockies and over the adjacent plains will
continue through early evening before diminishing. mpj

&&

.FIRE WEATHER...
A Red Flag Warning is in effect today from Noon to Midnight for
Zones 113 and 115. The combination of minimum relative humidity
values around 20 percent and gusty west winds sustained at 15 to
25 mph with gusts to 40 mph will create critical fire weather
conditions.

&&

.PREV DISCUSSION...
/ISSUED 535 AM MDT Fri Jul 25 2014/

Today through Sunday...Gusty westerly winds will persist today along
the Rocky Mountain Front and adjacent plains as an upper-level low
over southern Canada gradually shifts east. Have continued the High
Wind Warning through this afternoon for the Northern Rocky Mountain
Front and eastern Glacier county. Breezy west winds of 20 to 30 mph
and gusts up to 40 mph are also expected in eastern portions of the
forecast area including Hill, Blaine, Chouteau and Fergus counties.
In addition to the breezy west winds, afternoon RH values near 20
percent will lead to critical fire weather conditions for Fire Zones
113 and 115 and have issued a Red Flag Warning from Noon today to
Midnight. By tonight, a ridge of high pressure will build into the
area allowing for winds to decrease. This upper-level ridge will
remain over the Northern Rockies through the weekend yielding mainly
dry and warm conditions as well as lighter winds. The only exception
is in far southwest Montana where limited Monsoonal moisture and
instability may trigger an isolated thunderstorm. MLV

Sunday night through Friday...Montana will remain beneath an upper
level ridge for the entire forecast period. This pattern will lead
to mostly dry conditions with increasing temperatures through
mid-week as the ridge axis remains over the Northern Rocky
Mountains. Wild card in this pattern will be how much monsoonal
moisture will be able to work it`s way northward along the leading
edge of the ridge. Pattern suggests that isolated thunderstorm
activity could be possible in far Southwest Montana through much of
the period. However, the best chance for isolated convection to work
it`s way into Central Montana appears to be later in the week as
models depict a disturbance moving northward through the Great Basin
Wednesday and moving into Western Montana on Thursday. Confidence in
timing and coverage is low at this time, especially given the
strength of the upper ridge. Main impact during the upcoming week
will be the continued curing of fuels and the increasing likelihood
that despite the low chances for thunderstorm activity, any storms
that do form will be dry thereby increasing fire danger. mpj

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  79  49  80  51 /  10   0   0   0
CTB  74  47  76  48 /  10  10   0   0
HLN  81  53  83  54 /   0   0   0   0
BZN  80  44  82  46 /   0   0   0   0
WEY  73  34  75  37 /   0   0   0   0
DLN  78  46  81  48 /   0   0   0   0
HVR  81  51  79  51 /  10  10  10   0
LWT  80  49  78  51 /   0   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING until Midnight MDT tonight Blaine...Chouteau...
Fergus...Hill.

HIGH WIND WARNING until 3 PM MDT this afternoon Northern Rocky
Mountain Front.

HIGH WIND WARNING until 3 PM MDT this afternoon Eastern Glacier.

&&

$$

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