Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 051044

Area Forecast Discussion
National Weather Service Denver/Boulder CO
344 AM MST Tue Dec 5 2023


-  Mild and dry through Thursday.

- The next system arrives Friday bringing light to moderate snow
for parts of the mountains and valleys. By Friday evening, light
snow could spread into parts of the I-25 corridor and eastern

- Cooler temperatures persist Friday through early next week.


.SHORT TERM...(Today and tonight)
Issued at 343 AM MST Tue Dec 5 2023

We`ll have a quiet day today as a ridge of high pressure builds
east over Colorado. Flow aloft will be decreasing, but 30-40 knot
winds in the 600-50 mb layer will still be enough to feed some
wind down the east slopes of the Front Range. Other areas will not
have much wind. The remaining clouds trapped against the ridges
should continue to dissipate and will likely be gone by early
afternoon. We`ll still have some thin cirrus and a few fragments
of wave clouds over the Front Range, but it will be a pretty sunny
day. Forecast temperatures are about the same as yesterday on the
plains, and 5-10 degrees warmer in the mountains, and those look

.LONG TERM...(Wednesday through Monday)
Issued at 343 AM MST Tue Dec 5 2023

Subsidence continues across the region. A strong upper level ridge
remains in place through Thursday evening. Wednesday will likely be
the warmest day this week as 700mb temperatures approach 6-8C.
Surface temperatures range from low to mid 60s for the plains and
mid 30s to mid 40s for the mountains/valleys. Areas across the
foothills and plains trend at least 8-15 degrees above normal.
Although these temperatures will likely not break records, a few
eastern cities in the plains will be close such as Limon (Record 68
in 1981). As mostly clear skies continue into Thursday, our Sangster
pressure gradient model indicates increasing probabilities of
wind gusts exceeding 60kts starting Thursday morning through late
evening. This also evident throughout both cross sections
displaying strong vertical velocities favoring a uniform westerly
flow and tight pressure gradients. Thus there is agreement with
the previous shift where wind gusts up to 65-70 mph could reach
near high wind criteria for the mountain tops and adjacent
foothills. Additionally, an slight increase in mid-level moisture
will likely lead to a few photogenic mountain wave clouds.

Starting Thursday night, the next trough enters Utah and pushes into
Colorado Friday. There is still a bit of disagreement in QPF amounts
but overall, weak upslope and favorable forcing should lead to
light to moderate snow for the mountains, valleys, and foothills.
Depending on the speed of the trough and if it deepens (GFS
solution), then light snow could continue to spread to the plains
through Saturday morning. Either way, this forecast package
includes increasing chances of snow across Park County and the
Palmer Divide given the sinking movement of this system. Amounts
are light but given the potential for light snow during rush hour
on a Friday evening, prepare for slick roads and lower
visibilities especially across mountain passes. As the bulk of
moisture exits Saturday afternoon, another shortwave arrives
Sunday morning which will likely lead to another round of light
snow for the mountains. Ensembles favor cooler temperatures
through early next week.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 343 AM MST Tue Dec 5 2023

VFR through tonight. Southwest winds will become light east or
northeast around 18z. There may be a couple hours of
light/variable winds in between. S/W drainage winds should
resume by 02z.




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