Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 260610

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1110 PM MST Fri Nov 25 2022

Issued at 812 PM MST Fri Nov 25 2022

It`s another quiet evening across northeast Colorado. Stuck on the
fringes of a cutoff low near southwest Texas and stronger zonal
flow to our north, there`s very little wind, moisture, or even
clouds to speak of for the moment. While that will change
tomorrow... the overnight hours will remain calm. Have made some
minor adjustments to the grids but otherwise the previous forecast
remains on track.


.SHORT TERM...(This evening through Saturday)
Issued at 202 PM MST Fri Nov 25 2022

Into Saturday, flow aloft develops a westerly component in response
to a weak shortwave trough approaching from the west. Although not
strong, there will be cross-barrier flow over the high mountains
which will support breezy conditions in those areas Saturday AM.
High-resolution guidance shows good agreement for gusts in the
30-40 mph range, but can`t rule out the chance for a few gusts
above 40 mph. It will be mild with highs in the 50s over the low
elevations, 40s for foothills, and 20s/30s for the mountains.

The weak shortwave nears closer to Colorado in the afternoon. Model
cross sections show shallow moisture developing in the high country
towards the afternoon period. With weak synoptic ascent and
orographics, this will support light snow showers in the mountains
in the afternoon extending into the evening. No major impacts are
anticipated, but showers could bring periods of wintery driving
conditions to the mountains. Meanwhile a cold front moves across
the plains in the afternoon from northeast to southwest accompanied
by enhanced northeasterly flow behind it. Plains will stay dry
for the afternoon period with breezy conditions over the eastern
plains with gusts 20-30 mph. Relative humidity will be on the
lower end; however, not near critical thresholds thus limiting
the chances for critical fire weather conditions.

.LONG TERM...(Saturday night through Friday)
Issued at 202 PM MST Fri Nov 25 2022

For Saturday night, there will be a weak upper level disturbance
that passes through Colorado in the northwest flow regime. Not
very impressive at this time with only weak synoptic scale QG
ascent, meager lapse rates and shallow and brief upslope flow
along the Front Range. Over the mountains there will be some
favorable northwest orographic flow of 10-20kt for much of
Saturday night before moisture becomes very shallow by 12z Sunday.
Snow accumulations look to be in the 1 to 2 inch range given the
overall weakness of the system. Best chance for accumulating snow
on the plains would be locations adjacent plains and further south
over the Palmer Divide. Trace amounts to up to an inch of snow
look to be the range on the plains with little or no snowfall
over the far northeast corner.

On Sunday, there will be a drying and subsident flow following the
weak Saturday night system. The main story will be the strengthening
westerly winds over the mountains on Sunday and Monday. Cross
barrier flow increasing 40 to 50 kt through the period and there is
some mountain top stability with some wave amplification
possible. For now will continue with potential gusts up around 65
mph over wind prone areas of higher mountains and foothills.
Could see a few higher gusts around 70 mph but for now won`t
issue any wind hilites.

The next potentially stronger system expected to impact the region
late Monday and Tuesday with light snowfall to the mountains and
probably much of the plains as well along with much colder
temperatures. There is still some timing differences between the
models and there has been some agreement on a less amplitude and
energy with the system with more of a "brush by" approach. This
will favor again the mountains and locations further north towards
the Wyoming border areas. Biggest impact will be the colder
temperatures with readings only in the 20s for high temperatures
across the plains. Based on latest model trends snowfall expected
to be light on the plains, generally under 2 inches.


.AVIATION...(For the 06Z TAFS through 06Z Saturday night)
Issued at 1108 PM MST Fri Nov 25 2022

VFR through Saturday. Light winds will become northeast at 10-20
knots around 18-20z. ILS conditions are expected to develop
Saturday evening with scattered light snow showers.




LONG TERM...Entrekin
AVIATION...Gimmestad is the U.S. government's official web portal to all federal, state and local government web resources and services.