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Area forecast discussion
National Weather Service Denver/Boulder Colorado
826 am MST Fri Feb 24 2017

Update...
issued at 819 am MST Fri Feb 24 2017

Updated forecast for more snowfall this morning over the urban
corridor and plains with accumulations around an inch or less
over the urban corridor and 1-2 inches in the foothills. Still
seeing shallow upslope up to around 9000kt and still some wrap
around moisture from slow moving upper low over Nebraska. Could
also see some convective snow showers developing this afternoon
and early evening, especially in/near the foothills. May need to
further adjust pops upwards pending how the afternoon plays out.

&&

Short term...(today and tonight)
issued at 350 am MST Fri Feb 24 2017

Snow has diminished to flurries in most areas. However there is
some lift wrapping back around the upper low that is causing some
increase in the snow again over the southern Nebraska Panhandle,
and there are hints that this will continue to push into
northeastern Colorado this morning. Snowfall should be light, and
across much of the area this will only cause the flurries to
continue. Meanwhile cooler air aloft will spread into the central
mountains from the west. This will cause some light showers to
redevelop this morning, and a little heating should enhance these
during the afternoon. It looks like most of this should pass from
central Colorado toward the south of Denver where the coldest air
aloft should be, but there could be some showers moving off the
foothills further north toward the end of the day. Though this
should produce light snow in general, there may be enough
instability for a few of the showers to produce a quick inch or
two.

Any remaining snow should be fading this evening, with decreasing
clouds overnight. Temperatures will drop, though they will be
limited by developing south winds on the plains and decent
northwest winds over the mountain ridges and foothills. Coldest
spots could get fairly cold though, below zero in the mountains
and close to zero in valley spots on the plains.

Long term...(saturday through thursday)
issued at 350 am MST Fri Feb 24 2017

Models have flat, weak upper ridging over the County Warning Area on Saturday.
There is a weak upper trough to move across late Saturday night
into Sunday afternoon. The flow aloft is pretty much fairly weak
and zonal all four periods. The synoptic scale energy is weak
downward motion on Saturday. There is a bit of upward motion
Saturday night, but it is weak. There is downward motion Sunday
and Sunday evening, with upward again overnight Sunday night. The
boundary layer winds are weak and downsloping on Saturday. There
could be a bit of weak upslope Saturday night associated with the
weak upper trough. There is a northwesterly downsloping early
Sunday, then pretty much normal diurnal trends seem likely the
rest of Sunday and Sunday night. For moisture, Saturday starts out
pretty dry. By afternoon, moisture increases in the mountains,
but it is not very deep. This continues Saturday night into early
Sunday morning. The plains have some mid and upper level
cloudiness Saturday afternoon and night. By mid morning Sunday,
the mountains dry out, with just some mid level moisture for the
plains by afternoon. For Sunday night, there is a bit of moisture
in the mountains. The quantitative precipitation forecast fields show limited measurable snowfall
over the mountains Saturday afternoon into Sunday afternoon. For
pops, will go with 30-60%s in the mountains Saturday afternoon
into early Sunday morning, then 10-30%s after that through 12z
Monday. No pops for the plains. The snow model gives meager
accumulations in the mountains. For temperatures, saturday's highs
are 2-5 c warm than today's highs. Sunday's highs are 0-2 c
warmer than saturday's the models are showing some consistency
with the lack of warming for the next few days. For the later
days, Monday through Thursday, models have west- southwesterly
flow aloft Monday, then an upper trough moves across late Monday
night into Tuesday evening. The European model (ecmwf) is slower with this feature.
West- northwesterly flow aloft dominates Wednesday and Thursday
with little moisture. Tuesday's trough does not look like it will
provide any precipitation for the plains at this time. But maybe
that will change? Temperatures stay below seasonal normals through
Wednesday.

&&

Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 819 am MST Fri Feb 24 2017

Light snow covers all local terminals this morning with vsbys
generally in the 2-3 mile range and ceilings around 1000 feet.
These conditions will remain through much of the morning with
possible brief improvement towards the noon hour. Still could see
some convective snow showers developing this afternoon for more
snow showers. Snow accumulations around an inch or less, possibly
up to 2 inches in heavier convective snow showers.

&&

Bou watches/warnings/advisories...
none.
&&

$$

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