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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
1024 PM MDT Tuesday Oct 6 2015

issued at 1016 PM MDT Tuesday Oct 6 2015

Band of showers and storms holding together over northeastern
Colorado...some uncertainty if it will make it all the way to the
corner. Meanwhile plenty of weaker convection over the central
mountains that continues to regenerate. Raised probability of precipitation throughout
based on current activity...still showing a decline towards
morning. Pulled fog out of Denver as we are expecting south winds
most of the night...still expecting some areas of fog across the
rest of the plains.


Short term...(this evening through wednesday)
issued at 242 PM MDT Tuesday Oct 6 2015

Forecast pretty much unfolding as expected with regard to showers
and storms becoming more organized across the Front Range
foothills and Palmer Divide area and spreading northeast across
the Front Range urban corridor. However...persistent clouds and
stratus deck have kept temperatures much cooler. In any
case...there is still enough upper level divergence associated
with the left exit region of the upper jet for an organized area
of showers and thunderstorms to continue to spread northeast
during the course of the evening. Still not sure if one main batch
of showers will move away from the Front Range early this
evening...or if there will be another round or two developing
behind...but enough synoptic scale support to carry high probability of precipitation
through the early evening hours. Heavy rainfall is possible with
amounts up to 1 inch in 30-45 minutes from the strongest isolated
storms. Chances will then gradually decrease late in the evening
and overnight as airmass stabilizes and best upper level
divergence exits the forecast area.

The stratus deck was barely budging even with the convection
coming over the top. Low level airmass will remain quite moist
with the showers and storms...which will support areas of fog
redeveloping overnight. Not sure how thick and widespread it will
be though with stratus deck already in place.

For Wednesday...morning stratus and fog will gradually burn off
with a drier airmass taking hold by afternoon. Temperatures should
also respond nicely to the return of sunshine...but have cut back
temperatures a couple degrees from guidance due to morning clouds and more
moisture in the ground. Any chance of precipitation seems to be
lowering with each successive model run...but will hang onto low
probability of precipitation over the mountains/Palmer Divide area where airmass will
become slightly unstable.

Long term...(wednesday night through tuesday)
issued at 242 PM MDT Tuesday Oct 6 2015

Any remaining showers and few thunderstorms will push southeast
out of the area and diminish Wednesday night.

As a ridge aloft begins building in from the Pacific off of
California...a shortwave in the northerly flow aloft will dive
south out of Alberta along the Front Range of The Rockies. This
will push a cold front into the area Thursday with light upslope
flow over the plains. Expect slightly cooler temperatures and a
slight chance of showers over the Front Range mountains. Clouds
should clear overnight allowing for radiational cooling over the
plains...have kept readings below guidance. Mountains will
experience minor warming as warm advection moves in from the

The ridge aloft will bring warm and dry weather Friday through
Sunday...with readings about 10 degrees warmer than average this
weekend. Zonal flow over the northern US will then sink south as a
trough pushes across Canada into the Great Lakes putting the state
in slightly cooler northwesterly flow aloft. Dry weather looks to
hold on through Tuesday.


Aviation...(for the tafs through 06z Wednesday evening)
issued at 1016 PM MDT Tuesday Oct 6 2015

Areas of IFR ceilings will become more widespread
overnight...expect low surface visibilities will mainly stay north
of Denver. Ceilings lifting to MVFR around 15z...expect VFR after


Bou watches/warnings/advisories...


short term...barjenbruch
long term...kriederman

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