Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 160411

Area Forecast Discussion
National Weather Service Denver/Boulder CO
911 PM MST Sun Jan 15 2017

Issued at 911 PM MST Sun Jan 15 2017

Snow has spread over most of our area as the airmass has
saturated, but there is not much lift so in most places the snow
is very light. Short term models show some weak banded features
coming and going overnight, but even if these are real the
resulting snow should still be light for the next 6 hours.

Main event will be the deformation zone lifting north as the low
moves toward eastern Kansas. Still some differences in models as
far as the structure of this in the morning, but there is still
agreement in increased lift spreading northward which should at
least produce a period of accumulating light snow in Denver late
tonight and Monday morning. Still a few runs that have more snow
coming up as far as Denver, but consensus of holding the heavier
snow mainly south and east of Limon looks like the right idea.
Hanging on to the advisory at this point for a couple of reasons.
There is still a decent chance of getting several inches of snow
in a few hours across the area, and there is still lingering
impact from a little freezing rain that fell earlier today.
Only minor changes at this point, mainly for higher PoPs but lower
accumulations overnight.


.SHORT TERM...(This evening through Monday)
Issued at 305 PM MST Sun Jan 15 2017

An upper level low currently over southern New Mexico has brought
an increase in moisture in southerly flow. The first initial wave
of the storm system has pushed through the forecast area today
bringing a wintery mix of rain, snow, sleet and freezing rain.
Additional waves of moisture are expected to push into the area
this evening and overnight as the storm system moves into Kansas
by Monday. Some mid-level warming is still expected this evening
over the eastern plains, so will keep a chance of freezing rain
over the far eastern plains in the forecast.

Additional snow will push into northeastern Colorado overnight.
Models have trended to show slight upslope 700 mb flow overnight
and into Monday morning with additional waves of moisture moving
in. Have increased PoPs along the Front Range as well as snow
amounts expected. Models still all over the place with snow
amounts expected, with each other and within themselves. Overall,
expecting 1 to 3 inches of snow for the urban corridor and 2 to 4
inches over the eastern plains, with the higher amounts expected
south and east of I76. Depending on the speed and orientation of the
waves of moisture, could see another inch or two of accumulation in
certain places. The high country, especially along and east of the
divide should light to moderate snow in this set up through Monday
morning, with 2 to 6 inches expected. Temperatures Monday will be
similar to today`s readings, though cooler in the mountains. Have
gone slightly cooler than guidance over the plains with expected
cloud cover and snow. Northerly winds are expected to increase over
the plains Monday as high surface pressure pushes down along the
Northern Rockies. Gusts of 15 to 30 mph will likely produce some
blowing snow over the plains.

.LONG TERM...(Monday night through Sunday)
Issued at 305 PM MST Sun Jan 15 2017

Storm system will continue to pull away from the region. There is
some lingering moisture under the piece of upper trough that
holds back over Colorado, but at this time only expect a few
light snow showers into the early evening hours over the southern
portions of the forecast area. Then skies will clear. With light
boundary layer flow and high dewpoints would expect fog to form in
low lying areas, including the high mountain valleys and South
Platte River valley Monday night into Tuesday morning.

Tuesday, Wednesday, and most of Thursday will feature a calmer
weather period for a change. Warmer and dry weather will occur with
a sharp ridge axis over the forecast area. Temperatures will rise
above normal with highs pushing 60F along the Front Range by

The next chance of precipitation may reach the mountains by
Thursday night and the plains Friday as the next in a series of
storm system breaks down the ridge. The first wave is expected to
be weak but a couple stronger storms would be possible Saturday
into early next week. Temperatures will likely return to near
normal levels with a better chance of snow with each of these
storms. Hard to get caught up in any details for sure this far out
given uncertainty in these waves with regard to timing, location,
and intensity.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 911 PM MST Sun Jan 15 2017

MVFR conditions in light snow will prevail through Monday morning.
There will likely be a few periods of IFR conditions between 07z
and 15z, when the snow may increase a bit. The snow should end
between 15z and 18z with accumulations of an inch or two. VFR
conditions expected after that.


Winter Weather Advisory until 11 AM MST Monday for COZ041-046-



SHORT TERM...Kriederman
LONG TERM...Barjenbruch
AVIATION...Gimmestad is the U.S. government's official web portal to all federal, state and local government web resources and services.