Area Forecast Discussion
Issued by NWS Great Falls, MT

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FXUS65 KTFX 292328

Area Forecast Discussion
National Weather Service Great Falls MT
528 PM MDT FRI JUL 29 2016



will continue to build into North Central and Southwest Montana
through tonight, which will keep most of the area dry. However,
daytime heating has caused isolated weak thunderstorm to develop
over some mountain areas of North Central and move just off the
mountains. Am anticipating these storms to generally diminish
after 7 or 8 pm. An upper level low pressure trough will then move
east across British Columbia and into Alberta Saturday into
Saturday night, bringing an increasing southwest flow aloft to the
area. Weak energy in the flow will combine with a weak cold front
approaching from the northwest and daytime heating to bring
another chance for isolated thunderstorms Saturday afternoon and
evening, mainly over and near the mountains. A relative lack of
available moisture will limit potential storm coverage. As the
trough moves east across Alberta into Saskatchewan on Sunday and
in the wake of the passing cold front, west to northwest winds
will become breezy across much of the area. There will also be
another chance for isolated thunderstorms in the vicinity of the
cold front in the mountain areas of Southwest Montana, as well as
along the Hi-Line closer to the low pressure center. Temperatures
ahead of the trough on Saturday will warm to between 5 and 10
degrees above normal, but the passage of the cold front will cool
temperatures closer to normal on Sunday.  Coulston

SUNDAY NIGHT THROUGH FRIDAY...Period begins with a closed upper
level low tracking east across central AB/SK Sunday night.
Associated upper level jet energy tracks east along the
US/Canadian border with some lingering showers possible near the
border while drier air moves in from the west across central/SW
MT. Upper level ridging builds in the wake of this system Monday
before another upper level low moves onshore Tuesday, taking a
slightly further south track eastward just north of the border
Tuesday night and Wednesday. Surface cold front looks to shift
east across the region Tuesday for a somewhat better chance of
showers/thunderstorms, through moisture is limited and better
upper level dynamics again stay along or just north of US/Canadian
border. Upper level ridging rebuilds again behind this system on
Thursday and Friday. Temperatures will remain warm and slightly
above seasonal averages Monday and Tuesday with slight cooling
occurring Wednesday before temperatures climb back above normal
again late next week. Hoenisch


.AVIATION...Updated 2328Z.

A high pressure ridge will keep the air mass warm and generally
stable. A low pressure shortwave will move into the Pacific
Northwest tonight and winds aloft will strengthen across the Rockies
ahead of this system. This will bring some breezy conditions along
the slopes of the Rockies and adjacent plains along with afternoon
gustiness at the surface. VFR conditions will prevail through the
next 24 hours.



Warm and very dry conditions will persist through this weekend,
but a passing shortwave trough will increase westerly winds aloft,
and, consequently, westerly surface winds, Saturday into Sunday.
Winds will be especially gusty along the east slopes of the
Rockies and over the adjacent plains. Afternoon humidities will
fall well into the teens on both Saturday and Sunday as well. This
combination of breezy and dry conditions will increase fire
concerns, especially on Sunday, when winds will be the strongest.
However, as of Friday, fire dangers are still mostly in the
moderate category across North Central and portions of Southwest
Montana, so fire weather highlights are not anticipated at this
time, but fire danger levels will continue to be monitored.


GTF  59  94  56  87 /  10  10   0  10
CTB  56  88  54  79 /  10  10  10  10
HLN  61  97  60  90 /  10  10  10  10
BZN  54  93  53  90 /  10  10  10  10
WEY  43  82  47  80 /  10  10  20  20
DLN  54  90  53  87 /  10  10  10  10
HVR  59  93  58  87 /  10  10  20  10
LWT  57  89  57  87 /  10  10  10  10



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