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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
210 PM MST Friday Feb 27 2015

Short term...(this evening through saturday)
issued at 126 PM MST Friday Feb 27 2015

For tonight...a relatively moist westerly flow aloft will be
over Colorado. Persist overrunning light snow has continued in
the mountains with a couple of inches at the ski areas today.
This will continue into the evening so will keep likely probability of precipitation going
at least in zone 34 through this evening...with another 1-2 inches
possible. Across the northeast plains...some nagging stratus and
pockets of light snow trapped under an inversion through the day.
Gusty south-southeasterly winds across the northeast plains but Highway cams do
not show much impact from blowing snow. Denver cyclone will
continue overnight with the models showing low boundary layer moisture
wrapping into the Denver area late tonight into Saturday
morning...10-16z. Not sure if it will be a low stratus deck for
fog...for now will hedge things towards stratus but also mention
patchy freezing fog. Weak middle and upper level qg does start to
advect into the mountains from the west on Saturday as the next
upper trough drops into the Great Basin. Will keep the mention of
snow with accumulations in the 1-4 inch range for the mountains...
favoring zone 34 the most. As for the northeast plains...the cold
front does slip into Denver in the afternoon...with northeasterly upslope winds
in the afternoon. Should see light snow developing in and near the
foothills and Palmer Divide after 21z.

Long term...(saturday night through friday)
issued at 126 PM MST Friday Feb 27 2015

An upper level low will slowly move south across California Saturday
night through Monday. This will keep a southwest flow aloft over
Colorado. For Saturday night...a weak wave embedded in the flow
aloft will move across Colorado. Meanwhile...a surface high will
move from the northern rockies southeast to the Central Plains
Saturday night and Sunday. This will keep a weak north to northeast
upslope low level flow over northeast Colorado. Lift from the wave
and low level upslope along the Front Range will produce light snow
Saturday night and early Sunday. May also get some lift from the jet
axis as it shifts north across Colorado. Expect up to 3 inches along
the Front Range...with a little less over the eastern plains.
Mountain top level winds will increase Sunday behind the wave
helping to produce orographic snow. Expect totals to be a little
higher in the mountains since it will snow longer...generally 2 to 6
inches for Saturday night and Sunday time frame.

On Monday...models showing heavy snow over the mountains of western
Colorado associated with a deep moist strong southwest flow aloft.
This is expected bring snow to parts of the north central mountains.
If flow backs too southerly...the northern central mountains may
miss out on a good part of the heavy snow. Over the plains...
southerly flow will warm temperatures and bring dry conditions.

As the upper level trough fills and moves inland...flow aloft will
turn more westerly and bring a better chance for snow to the
mountains Monday night and Tuesday. In the meantime...a strong wave
will drop south across the northern rockies and into the central
rockies Tuesday night. A cold front will accompany the wave from the
north. This is expected to bring a round of widespread snow Tuesday
and Tuesday night. The airmass behind it will be cold. Snow is
expected to taper off early Wednesday as the upper level system
moves east of the area. Highs will struggle to climb above 20
degrees Wednesday. If it clears out Wednesday night...sub zero lows
will be possible.

For Thursday and Friday...there will be a break from the snow and
cold. An upper level ridge builds over the Great Basin and produces
a dry northwest flow aloft over Colorado. Temperatures will
warm...but are still expected to be slightly below normal. The
warming trend will continue into Friday with highs expected to be
around normal with upper 40s and lower 50s expected over northeast


Aviation...(for the tafs through 00z Saturday late afternoon)
issued at 126 PM MST Friday Feb 27 2015

Low stratus trapped between the airports over Denver this afternoon.
With a weak Denver cyclone in place and no mixing to speak
of...this moisture will not be going as anywhere. As a result...
prevailing VFR with occasional ils/MVFR ceiling/visibility restrictions due to
stratus and lingering snow flurries. After 09z tonight...a better
area of low level moisture gets entrained in the cyclone and
funnels into Denver. Should get IFR ceilings developing...along with
patchy freezing fog. For now will go with vcfg wording in the tafs.
Low clouds will linger through the morning with a front around
20z...and a better chance of snow develop afterwards.


Bou watches/warnings/advisories...


Short term...Cooper
long term...meier

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