Area Forecast Discussion
Issued by NWS Glasgow, MT

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FXUS65 KGGW 270229

Area Forecast Discussion
National Weather Service GLASGOW MT
829 PM MDT FRI AUG 26 2016

.SHORT TERM...for northeast Montana...tonight through Sun...

Shaped up the weather elements to the current situation and
updated to clearing skies across the region for the overnight
hours. Little other adjustments were needed at this time. The
diurnal showers are ending quickly this evening. Proton

Previous Discussion...
Synoptic Setup: Short term begins with the base of a trough
moving through northeast Montana and running into Saskatchewan and
northern Manitoba. The High pressure heat dome is beginning to
reform over Nevada with the ridge running up into Washington and
British Columbia. Northwest flow resides between these two large
key features.

This afternoon and evening: trough will continue to mosey through
the area and bring a few scattered rain showers and isolated
thunderstorms until roughly sunset when activity should taper off
very fast.

Saturday morning through Sunday: Flow will transition to northern
to northwestern briefly Saturday morning with dry semi-cool air
moving in behind the trough. This will begin dry conditions across
the region however the ridge to the west will be hot on its heels
and simply reinforce the stable dry pattern through Sunday with
a gradual warming trend over the weekend. GAH

.LONG TERM...Sun night through Fri...
The long term period as described below remains fairly in tact.
Expect a developing ridge pattern to unfold over the region as a
trough digs into the Pacific northwest toward Midweek. This will
lead to dry and warm to hot conditions through much of the long
range. In fact, the latest consensus blended guidance did produce
somewhat warmer temperatures than what was inherited in the newly
populated grids.

As the ridge axis pushes east, flow aloft will turn more
southwesterly. This will allow for increasing shower activity.
There is a degree of uncertainty as to when precisely this may
occur late next week or into the weekend. Therefore, will have
slight chance pops to finish out the period in order to cover the
reduced confidence that exists by day 7 and 8. However, as is
obvious increasing spread in guidance solutions is fairly typical
out at larger time scales. Maliawco

Previous Long Term Discussion...
Zonal upper flow pattern over the northern CONUS early next week
will amplify through the week as a trof digs south along the
Pacific coast. Temperatures will warm through midweek with
generally dry condition expected as an upper ridge builds into the
northern plains.

Thunderstorm potential returns to the region by Wednesday
afternoon with the ridge axis shifting into the Dakotas. Southwest
flow aloft will push weak shortwaves embedded in the flow across
the region. Low level southeast flow will bring some moisture into
the state but not as favorable as earlier in the summer. Overall
expect high based storms with little qpf from Wednesday until the
upper trof moves into state. This may be as early as next weekend
but could be later as models not in good agreement. Ebert



VFR CIGS and VSBYS will prevail throughout this TAF period.
A few scattered showers and perhaps a rumble of thunder will
remain possible through the night-time hours for KSDY and KGDV.
Temporary reductions in VSBY are possible with steadier shower
activity. West to northwest winds around 10 kts becoming gusty in
and near convective weather are expected to drop off becoming
light after 03z. Maliawco/Mickelson




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