346 
FXUS65 KBOU 302140
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
240 PM MST Tue Nov 30 2021

.SHORT TERM...(This evening through Wednesday)
Issued at 240 PM MST Tue Nov 30 2021

High clouds continue to spread in from the north and they are
pretty thick under the nose of the jet moving off of the Rockies
this evening. These clouds will likely persist through the
evening, then thin somewhat as the best lift moves east. There are
still a lot of thinner high clouds behind the main area though, so
we've continued to increase the cloud cover through the day
tomorrow. The clouds should affect tonight's lows, so we've
moderated them a little, especially in the colder areas. If there
isn't some thinning of the clouds later tonight the lows will 
need to be raised some more. Likewise, highs on Wednesday may
hinge on how thick the clouds are. The air mass would support
near record highs in the lower 70s on the plains if it were sunny
with a little breeze. We'll probably be just shy of the records
and the current forecast looks alright.

The passing of the jet max this evening brings a strengthened mid
level inversion and a short lived increase in flow as low as
600-700 mb. This should produce a period of mountain wave
enhancement over the Front Range. The current forecast handles
this well although we could get a little more wind into the lower
foothills where that tends to happen, i.e. down the hill to Rocky
Flats and Boulder.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 240 PM MST Tue Nov 30 2021

Strong persistent ridge will remain centered over the Great Basin
through Saturday with weak flow aloft across Colorado. This will 
keep warm and dry conditions in place. Thursday looks very warm 
for December with highs in the lower to mid 70s over northeast 
Colorado. A few record highs could be reached. For Denver, the 
record high is 74F degrees. Airmass will continue to be very dry 
with only a few highs clouds expected. Will see a cool down for 
Friday when a weak cold front pushes through. Highs fall 10-15F, 
which is still about 15F above normal for this time of year. For 
northeast Colorado, this puts highs around 60 degrees. Mild 
temperatures continue Saturday. Flow aloft begins to increase as 
an upper level trough moves across the Northern Rockies. Could see
winds increase later Saturday and Saturday night. Another weak 
cold front moves through for Sunday. This knocks temperatures down
a little with highs in the 50s expected. 

The weather pattern for early to mid next week looks quite 
uncertain at this time. Models are in agreement with a 
system/upper level trough tracking southeast across the 
intermountain west. Little to no agreement on what this will look 
like yet, but this will be the first system in nearly two weeks 
that could bring precipitation to the area. Monday still looks 
mild and dry ahead of the storm system. Tuesday's weather will 
depend on the trough and it's timing. For now will have low PoPs 
in the forecast with slightly cooler temperatures. Can't rule out 
one more warm day Tuesday if this system ends up being a little 
slower.

&&

.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)
Issued at 1111 AM MST Tue Nov 30 2021

VFR through tonight. There's some uncertainty about wind direction
late this afternoon as southerly winds may become briefly north or
northeast between 22z and 02z. If this happens, speeds will be
less than 8 knots. Normal S/W drainage winds will resume this
evening.


&&

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

$$

SHORT TERM...Gimmestad
LONG TERM...Meier
AVIATION...Gimmestad