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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
840 PM MST Thursday Feb 26 2015

issued at 826 PM MST Thursday Feb 26 2015

Widespread light snow continues across much of northern Colorado
this evening. There is some slight diminishment south Denver and
Douglas County as stronger south to southeast low level flow
develops. Profilers/VAD winds confirm this with as low level flow
continues to turn more southeast. However...north and east of the
circulation center here continues to be some embedded areas of
moderate snow mainly east Denver and up through Aurora and dia.

The upper trough is moving slowly and qg fields suggests still show
weak upward ascent through much of the night. Main to change to
evening forecast was to delay some of the snow diminishment
overnight. Any additional snowfall will still be light...mainly in
the 1-2 inch range.

Update issued at 631 PM MST Thursday Feb 26 2015

Low level circulation showing up nice on radar and observations
early this evening over southern portions of Denver. There has
been some northward movement of the circulation during the past
hour and now into Aurora. There is some moderate to heavy bands
just north of the circulation around dia and points to the east
across eastern Adams County. The rest of the urban corridor
continues with just light snow with embedded bands of moderate
snow. Current forecast still looks on track with 1-3 inches.
Latest hrrr seems to have a pretty good handle on the circulation
and the heavier snow bands. No changes at this point.


Short term...(this evening through friday)
issued at 136 PM MST Thursday Feb 26 2015

Radar echoes starting to fill in around Denver as the next system
approaches the region from the northwest. Weak upslope coupled
with weak middle to upper level qg ascent will be in play through
this evening. Additional accumulations of an inch or less through
the rest of the afternoon...with another 1 to 3 inches this
evening. Best accumulations will be in and near the foothills and
Palmer Divide. In the high country...Ridgetop winds will be more
westerly overnight. The mountains could pick up another 2 to 5
inches overnight. Best middle level instability tonight will be west
of The Divide with 700 mb/500 mb lapse rate 7.5-8c/km snow
there will be more convective. East of The Divide...more of an
overrunning situation. Winds and snow accumulations should be
under advisory criteria tonight so no highlights planned at this
time. On Friday...the system shifts to the south and east with
decreasing snow coverage through the day. Across the northeast
plains...a fairly decent southeast to northwest surface pressure gradient sets up
especially to the east and southeast of Denver. As a
result...there could be some areas of blowing snow in the
afternoon with gusts of 25-35 miles per hour possible. Temperatures will
remain cold with wind chill temperatures from 5 to 10 below zero
in the windier areas...primarily the i70 corridor east of Denver
to the Stateline.

Long term...(friday night through thursday)
issued at 136 PM MST Thursday Feb 26 2015

On Friday night...the jet stream will be over the Desert Southwest
and southern rockies. This is expected to keep most of the snow to
our south...over southern Colorado and New Mexico. As the jet stream
shifts north late Friday night and Saturday snow is expected to move
into the mountains of north central Colorado. Will keep low probability of precipitation in
the forecast...mainly for the mountains Friday night and early
Saturday. Will then increase probability of precipitation as the jet moves over the area
Saturday afternoon and night. In addition to the jet...low level
winds will turn north to northeast Saturday and Saturday evening and
produce weak upslope lift. Not a strong push like the previous just expect light to occasional moderate snow. Best
accumulation should be over the mountains.

For Sunday and Monday...southwest flow will prevail as a broad upper
level trough remains over the southwest part of the country. Best
chance for snow under this pattern will be over the mountains. Will
keep low probability of precipitation in the forecast for the area...mainly for the chance
of light snow.

There will be a better chance for snow Tuesday and Wednesday as
another system drops southeast across the area. If this pans out...
this will push a cold front through the area and bring a period of
snow. Timing is still uncertain this far out...but still looking
like a period of snow for much of the area.

On Thursday...upper level ridge will build over the Great Basin and
produce a northwest flow over Colorado. It will be dry...but still
cool under this pattern.&&

Aviation...(for the tafs through 00z Friday late afternoon)
issued at 136 PM MST Thursday Feb 26 2015

Prevailing MVFR/IFR ceiling/visibility restrictions through 06z
tonight...lingering a bit longer at kbjc and kapa. Conditions
deteriorating already this afternoon with prevailing visibilities less
of a mile likely after 00z this evening. Snow coverage will
decrease overnight. Surface winds primarily E/sely. Some stronger
gusts possible at kden Friday areas of blsn may also be
an issue after 18z if some stronger gusts 20-25 kts develop.


Aviation...(for the tafs through 06z Friday evening)
issued at 826 PM MST Thursday Feb 26 2015

Ceilings/visibilities continue to very slowly improve at apa/den as more
south to southeast flow develops. In fact already seeing southwest
winds at apa. Lower ceilings and bjc with continued north to northeast
low level flow. Main change to upcoming tafs will be to keep the
light snow in the terminals a bit longer than current as snow
appears to be slow to end from the north. Additional snowfall will
be around an inch or less...highest at bjc and lower at apa.


Bou watches/warnings/advisories...


short term...Cooper
long term...meier

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