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

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 217 PM MST Sat Feb 13 2016

VFR condition anticipated through 21z Sunday. North/northeasterly winds this
evening will transition to southwesterly by midnight. Will need to watch of
any low stratus/fog slips into kden this evening with the northeasterly
winds...however it does appear to be dissipating at this time.
By 12z Sunday..S/sely winds anticipated. Winds will transition by
12z Sunday. Middle and upper level moisture will increase Sunday afternoon
with west/northwesterly winds expected at that time. Some instability in the afternoon
could produce brief ils restrictions with occasional broken ceilings 050-060
kft above ground level after 21z.


Bou watches/warnings/advisories...


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

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