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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
800 PM MST Sat Feb 13 2016

issued at 800 PM MST Sat Feb 13 2016

Following the cold front as it raced south through Wyoming and now
pushing into the state. Looks like the far northeast plains will
see gusts in the 35 to 45 miles per hour range with the frontal passage...and
perhaps a few rain drops or flakes for a short period. Timing the
front looks to push through the Denver area around 930 to 10 PM
tonight with gusts up to 35 miles per hour briefly...then diminishing through
the rest of the night.

Update issued at 553 PM MST Sat Feb 13 2016

Strong and gusty west winds continue to work down the Front Range
and have actually spread a bit farther east across the plains as
colder air is scoured out. Peak gusts in wind prone areas right
in/next to the base of the foothills near 60 miles per hour...with gusts
30-40 miles per hour spreading onto the nearby adjacent plains. The downslope
ahead of fast moving cold front seems sufficient to keep winds
going for most of the evening before cold front arrives from the
north...Wyoming border toward 730 PM and Denver toward 10 PM.
Gusty winds also associated with this front and strong pressure
rises. Main forecast update reflects latest temperature changes
and increase in winds over the plains both ahead of and just
behind front.


Short term...(this evening through sunday)
issued at 217 PM MST Sat Feb 13 2016

A moderate to strong northwesterly flow aloft will be over the
region through Sunday. A weak short wave trough embedded the flow
aloft will brush across Colorado as it moves across Wyoming late this
afternoon and evening. Weak qg ascent with little moisture to work with so
no precipitation expected with this. Spatial cross-sections show a mountain
wave developing this afternoon/evening ahead of the trough then more
bora like overnight. No highlights but will keep some gusts to 60
miles per hour above timberline and in the foothills. A weak front will push
across the northeast plains this wind should be more
north/northeast in the evening. Will need to keep an eye on fog
north and east of Denver that has been slow to dissipate. There is
an outside chance some of this could slip back into Denver following
the front. Overall coverage should be patchy if it does develop.
On Sunday...the nose of a strong upper level jet slides across
northern Colorado Sunday afternoon with moisture increasing in the Front
Range mountains. Best accumulating snowfall will be along north
and west facing slopes north of Interstate 70...with middle level
lapse rates 7-8c/km in the afternoon. Strong winds persist through the
day so areas of blowing snow possible over the higher mountain
passes. Across the northeast plains...downslope west of I-25 may
negate precipitation there but isolated rain showers possible east of the
Interstate and closer to the northern border.

Long term...(sunday night through saturday)
issued at 217 PM MST Sat Feb 13 2016

A moist northwest flow aloft will be over Colorado to begin the
extended period Sunday evening. The jet axis will be over
northwest Colorado at 00z Monday putting the mountains under the
front left exit region of the jet. As the upper level ridge
intensifies over the western states...the jet axis will shift east
overnight and be over the Central Plains Monday. The moist
northwest flow will produce orographic snow over the mountains.
The best snow should occur Sunday evening when lift from the jet
is overhead. Once the jet shifts east...snow intensity should
decrease. Lapse rates will just be 5-7 c/km Sunday night
and Monday.

For the Front Range and eastern plains...isolated to scattered
showers will be possible Sunday evening as a short wave trough
moves across Wyoming and the jet moves across the area. Best
chance will be over the northeast plains...farther away from the
downslope. Any precipitation that occurs should be light. Windy
conditions are expected in the foothills Sunday night through
Tuesday morning. Windy conditions are expected to move onto the
plains Monday due to good mixing.

Moisture will decrease Monday night and into Tuesday. This will
cause snow to decrease and come to an end in the mountains by
Tuesday afternoon if not sooner.

Temperatures will warm some each day Tuesday through Thursday as
an upper level ridge moves across The Rockies. Highs on Thursday
will climb well into the 60s with some 70s also possible. An
upper level trough and Pacific cold front will bring a chance for
mountain snow and cooler temperatures for Friday. Temperatures
will remain above normal Friday behind the front and may climb
above 60 again on Saturday.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 800 PM MST Sat Feb 13 2016

Gusty west/northwest winds up to 25 knots expected for most of
the Front Range airports through 04z although they could lighten
up at times. Kbjc will see higher gusts near 35 knots possible.
Then fast moving cold front expected to arrive in the Denver metropolitan
area airports around 0430z with an hour or two of gusty northerly
winds to at least 30 knots. Then winds will weaken and turn more
easterly through 08z as surface high pressure builds in behind the
front. By 12z...light southerly winds should prevail and hold
through most of the day Sunday before possibly mixing sufficiently
to allow more westerly wind component after 21z. Enough
instability with next fast moving wave for a slight chance of
showers and brief ils Landing conditions after 21z Sunday.
Otherwise visual Landing conditions will prevail...with only a
slight chance of lower ceilings with passing cold front late this


Bou watches/warnings/advisories...


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

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