Area Forecast Discussion
Issued by NWS Glasgow, MT

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FXUS65 KGGW 300441

Area Forecast Discussion
National Weather Service GLASGOW MT
1041 PM MDT Wed Mar 29 2017

.SHORT TERM...for northeast Montana...tonight through Fri...
9PM Update:
Showers continue to move towards the region this evening, have
slowed up the progression into the CWA for the overnight hours and
early morning hours. Otherwise very little change in the forecast
for tonight.   Proton

Previous Discussion:

Near short-term discussion through Thursday: Nearly
zonal flow aloft over Montana tonight turns more from the
southwest early Thursday morning in response to a strong upper-
level trough moving over the Pacific Northwest states. This
weather system will be responsible for the rain showers expected
across NE Montana over the next few days.

Model agreement is excellent in keeping temperatures above
freezing throughout this event. Expecting only rain. Lately, model
precip solutions have come together with timing and placement to a
fairly good consensus. Thursday morning, a widespread area of rain
showers over southern Montana will extend through portions of
central Montana enough to sneak over into our Petroleum and
Garfield Counties. Thursday afternoon, models are hinting that
the precip begins to organize into some kind of a band of rain
showers through out CWA, either from south to north or from south
to northeast. Also seems like Thursday afternoon and evening
begins the time of rain showers being stalled over our area.
Details will still take a little more time to work out, but it
generally seems that locations NW of Malta and SE of Glendive will
receive less rain accumulation and locations in-between those two
will see more - up to 0.50 inch by late Friday night.


.LONG TERM...Fri night through Wed...
There weren`t many changes to the inherited long term forecast.
The extended period begins Friday night with an exiting upper
level trough continuing to bring some lingering precipitation
through early Saturday along the North Dakota border.

Zonal flow aloft will keep the area mostly dry through the rest of
the weekend before another trough moves into the area Monday
morning. The latest models differ some on precipitation amounts
and how far north the heaviest precipitation will make it...left
the forecast with the more southerly track for now. This system
will finally move out of the area Tuesday night. By the end of the
extended forecast time frame, models are continuing to show an
amplified ridge moving into the region, so we can expect drying
and warming conditions for the middle and end of next week.
Previous discussion...The extended period begins Friday night
into the weekend with largely dry zonal flow aloft across the
northern High Plains while a trough begins to dig into the Pacific

The trough will amplify early next week and shift east with models
bringing the trough axis over eastern Montana by late Monday
evening. This will offer plenty of dynamic forcing for ascent to
justify chance pops for much of the CWA.

While models differ on timing, some indications are that the
trough will head downstream while a ridge amplifies across the
western CONUS for the middle and end of next week with a return to
dry and warm weather conditions. However, there is enough
uncertainty in the ensemble members that keeping in slight chances
for pops in line with consensus model blends still makes sense at
this time. Maliawco


VFR conditions will prevail tonight with increasing clouds. Light
south to southeast winds will range from 5 to 15 kts. Maliawco




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