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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
940 am MST Friday Nov 27 2015

issued at 918 am MST Friday Nov 27 2015

Best I can tell form the various satellite picture curves...
observations and area radars...the low clouds...patchy fog...and
very light snow are scattered hit and miss all over the County Warning Area right
now. The wind field across the entire County Warning Area is very light with
strong high pressure over the eastern third of Colorado. Do not
need to change much so will keep the 20-50% probability of precipitation for light snow
going. Will make a few minor changes to probability of precipitation...temperatures...and
cloud cover.


Short term...(today and tonight)
issued at 329 am MST Friday Nov 27 2015

Broad upper low will remain across the Great Basin through at
least tonight with a strong southwest flow aloft over Colorado.
The trend for this morning is for diminishing banded snowfall over
the northeast plains. Regional observations showing ceilings are
thinning and areal extent of snowfall is also shrinking as we are
loosing the upslope flow and weakening dynamics. Still getting
some narrow banded areas of more moderate snowfall but even these
bands will be diminishing this morning. Any additional snowfall
will be under an inch so will cancel the advisories with upcoming
forecast package. Only very slow moderation in temperatures from
what we have now with afternoon readings still only around 20
degrees across lower elevations.

Water vapor imagery showing some drying aloft across Arizona and
just moving into southwest Colorado. This drying will work into
northern Colorado during the day as moisture becomes even more
shallow. There is another piece of energy now over Southern
California which rotate around the low and into western Colorado
later this afternoon and night. This will result in increasing qg
ascent...especially across the mountains this afternoon and
night. Despite the ascent...moisture levels are still shallow with
the drying aloft. This coupled with warming low levels may result
in some of that freezing drizzle again over the plains tonight.
The low level flow will shift more southeast tonight which will
favor park and Larimer counties for snowfall with a minimum north
of the Palmer Divide.

Long term...(saturday through thursday)
issued at 329 am MST Friday Nov 27 2015

Southwest flow aloft will continue Saturday as the upper low
over Utah remains nearly stationary while being stretched
southwest to northeast. Upward qg vertical velocity in the
morning will weaken and almost become downward...before becoming
upward again after midnight and strengthen as a jet rounds the
bottom of the low and into Colorado. At the surface...high
pressure over the Great Plains will weaken thereby weakening the
pressure gradient into NE Colorado...but still remain light
upslope. Light snow will be diminishing over the mountains with a
couple inches at best of accumulation. Over the plains...forecast
soundings show an atmosphere better at producing freezing drizzle
with a slight chance of snow flakes embedded during the
day...then moisture depletes overnight. Temperatures will be
slightly warmer Saturday...but still below freezing.

Models still struggling with handling the low on Sunday as it
pushes across the northern rockies. Believe the NAM is too fast
of a solution...have strayed away from its guidance at this
point. As the low pivots over the northern will
swing its southern section over the state and increase upward qg
lift. Forecast soundings don't look all that great for good
snow amounts..and possibly will continue to see areas of
freezing drizzle. However the atmosphere becomes unstable and
will think enough lift will be there for the airmass to moisten
and become snow. Temperatures will warm to right around freezing
for the plains.

Northwest flow on the backside of the low on Monday will keep
light snow going over the mountains while the plains dry out west
to east. Temperatures will be warming slowly with possible above
freezing temperatures. Tuesday and Wednesday will feature a
continued warming and dry pattern as an upper ridge moves


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 918 am MST Friday Nov 27 2015

Will keep ceilings at or below bkn030 for the rest of the day. Will
some -sn br off an on all day with visibilities at or above 2sm. Winds
should keep a east to southeast direction at speeds under 10
knots the rest of the day.


Bou watches/warnings/advisories...


short term...entrekin
long term...kriederman

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