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000
FXUS65 KBOU 021050
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
350 AM MST Tue Mar 2 2021

.SHORT TERM...(Today and tonight)
Issued at 234 AM MST Tue Mar 2 2021

For today the axis of the ridge continues to shift over the state
with increasing westerly flow aloft through the morning hours.
Cross barrier flow increases with a weak stable layer in place
allowing for some increased gusting up to 30 mph over the eastern
slopes of the higher elevations through the morning hours. By the
afternoon flow decreases but a weak frontal push from the north
will help to bring winds to the border counties and northern
foothills with gusts up to 35 mph possible. Another sunny day is
in store with temperatures about 5 to 10 degrees warmer than
Monday. Highs across the plains will reach into the lower 60s with
30s and low 40s expected in the high country.

Winds will continue to decrease through the day with another
chance for low level inversions setting up in the high mountain
valleys such as Middle Park overnight tonight. Lows overnight
will drop into the 20s over the plains with teens and single
digits in the high country.


.LONG TERM...(Wednesday through Monday)
Issued at 234 AM MST Tue Mar 2 2021

The weather will remain mild and dry Wednesday under a broad
ridge, with mostly clear skies and warm temperatures. Highs will
be in the upper 50s and lower 60s F on the plains and in the 40s
in the mountains. A closed low will come on shore over California
in the evening and approach CO by early Thursday.

Increasing SW flow aloft as the low approaches will likely have
little impact for NE CO early Thursday. However, model agreement
on the track and timing of the low have improved significantly
with recent model runs, putting the center of the low over SE CO
by Thursday afternoon. QG fields show moderate ascent of around 5
to 10 mb/hr at the surface increasing to around 20 mb/hr in the
mid levels in the afternoon, and we should also benefit from
decent mid level lapse rates of about 6.5 to 7.5 C/km across the
area. Models are also showing good precipitable water values with
the system. Snow should begin in the mountains early Thursday and
increase in the afternoon and early evening. Rain should spread to
the plains in the afternoon, changing to a rain-snow mix after
sunset. Snowfall will decrease overnight and diminish by Friday
morning. N to NE upslope flow late Thursday and early Friday may
favor the Palmer Divide near the end of the event.

The system will exit to the SE early Friday, with N flow and high
pressure aloft building back in behind it. Expect mostly clear
skies again and near normal temperatures Friday, with highs in the
upper 40s F on the plains near Denver. On the NE plains, highs
will be in the mid to upper 50s F.

It will be warm and dry over the weekend with the large ridge
moving slowly over the Rockies. Highs should be back in the upper
50s to mid 60s F on the plains. A shortwave will into the Rockies
but models still disagree about its placement and timing. The
ECMWF is still bringing the system in a little slower and further
S than the GFS, which would support some more light snowfall in
the mountains Sunday. The NBM seems to be leaning toward the ECMWF
solution with low PoPs for the mountains Sunday, and I have no
reason to contradict it. Any precipitation should diminish Sunday
night into Monday behind the shortwave and Monday should be mild
and dry with increasing SW flow aloft as the next trough comes on
shore over California. We might see some more light snowfall in
the mountains by Tuesday as that trough advances inland.

&&

.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 234 AM MST Tue Mar 2 2021

VFR conditions are expected through Wednesday morning. Winds will
mainly be out of the south to southwest through the TAF period
with normal drainage patterns this evening.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...Bowen
LONG TERM...Direnzo
AVIATION...Bowen