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Area forecast discussion 
National Weather Service Pueblo Colorado
327 PM MST Sat Feb 28 2015

Short term...(this evening through sunday)
issued at 252 PM MST Sat Feb 28 2015

Currently...an upper trough stretched to the SW from the Great Basin
to the West Coast...with the upper low located over central California. This
was streaming abundant moisture across the 4 corners and into
Colorado. A break in the cloud cover this morning provided for a
pleasant first half of the day...though temperatures remained cool and have
only warmed into the teens to middle 20s across the forecast area.
Clouds have been on the increase from the SW...and intermittent snow
is beginning to creep across the area.

Tonight and tomorrow...the upper low moves very little over the next
24 hours...and the plentiful stream of moisture remains constant. One
thing to note is that all the models indicate that snowfall is a
near certainty for the higher terrain...and especially along the
Continental Divide...so all highlights in place look good at this time. The SW
flow aloft will bring impressive snow amounts to SW facing
slopes...and areas such as Wolf Creek are expected to see snowfall
amounts measured in feet. As for the slv and eastern plains...short
range and hi res models all point to activity ramping up for 6-9
hours through the evening...then really tapering off through the
morning...and then slowly getting active again between 21z and 24z
Sunday afternoon. The moisture feed remains constant...but the trigger
seems to be dynamics and can be tracked via the vorticity fields.
However...having said all that...the atmosphere is primed to be a
very efficient snow/flurry maker...so am very hesitant to pull probability of precipitation
completely through the morning for the plains. Therefore...will keep
10 probability of precipitation during what is suspected to be lull periods. While snowfall
amounts will be impressive for the higher elevations...the slv and east
plains should see only an inch or two of new accumulation over the
next 24 hours. As for temperatures...no change there as cold readings
will persist. Moore

Long term...(sunday night through saturday)
issued at 252 PM MST Sat Feb 28 2015

..unsettled weather through Wednesday then warmer temperatures
return...

It is going to remain unsettled through at least Wednesday as the
trough over the western Continental U.S. Moves slowly east. Once this trough
passes the region on Wednesday...it will gradually start to warm up.
Highs in the 50s are likely to return by Friday. In the
meantime...it is going to be cold with on and off periods of snow
over the plains...with snow...very heavy at times...over the
mountains...especially over the SW slopes of the San Juans.

Sunday night into Monday...

A band of deep moisture and a moderate jet will be over the region
00z Monday (6 PM sunday). This is going to allow for heavy snow over
the San Juans Sunday evening with periods of snow over the remainder
of the region. This area of snow will gradually lift north through
the night and especially during the day Monday...so overall probability of precipitation
will gradually decrease over this time period. With that said...snow
over the Continental Divide will likely continue but the intensity will subside
somewhat Monday.

It is likely to become quite breezy to windy over regions of the
forecast area Monday as a lead trough moves over the region and the
gradient tightens up significantly. Winds over the
mountains...especially the San Juans....sangre Delaware cristos and the
wets will be quite strong...with gusts to 40 to 50 miles per hour likely. Pikes
Peak will also get gusty. Winds will also become quite brisk over
the San Luis valley and parts of the plains. On the plains...the
best chance for stronger winds will be south of a line from roughly
Trinidad to Lamar...and possibly the Palmer Divide. This wind will
allow things to mix out quite a bit and temperatures Monday are likely to
warm to around 40 most of the plains and valleys...with middle 40s over
the far southeast plains. Areas which remain cool will likely be the Pueblo
area. Given the strong flow...maximum temperatures on Monday are likely going to
be revised in later forecasts...with the windier areas likely warmer
than what the current grids show...while areas that do not see
much wind may be cooler than current grids show.

During the day Monday...little if any precipitation is expected on the
plains with most of the snow along the Continental Divide. Some snow will also
be at the higher elevations of the remainder of the mountains over the
forecast area.

Monday night into Tuesday...

It is likely going to be quite breezy/windy over the region Monday
night as the gradient aloft really tightens up. This will likely
keep it relatively mild on the plains...especially north of Highway
50 and east of the mountains very windy conditions are likely over all
of the mountains...with the strongest winds generally south of US-50. It
is not out of the question that the winter storm warnings for the
San Juans may need to be upgraded to a Blizzard Warning from late
Monday into early Tuesday.

It will be dry over the plains Monday night with snow over the
mountains heavy snow is possible along the Continental Divide.

During the day Tuesday a strong cold front will move down the
plains. This will decrease the surface winds...and moisture will
gradually once again increase over the plains. However...I expect
it to remain dry over nearly all of the plains until late in the
day Tuesday. Maximum temperatures will occur very early during the daylight
hours on Tuesday for the Pueblo and Colo Springs area...with temperatures
crashing below freezing during the late morning or early afternoon
time period. The overall warmest temperatures this day will occur in
extreme southeast Baca County.

As flow transitions for SW to northwest aloft during Tuesday...the heaviest
snow along the Continental Divide will develop over the central mountains.

Tuesday night into Wednesday...

It gets quite cold and snowy once again over the plains. Temperatures will
fall into the single digits by early Wednesday morning and widespread
light snow will likely be falling over most if not all of the
plains. Low at 700 will be westerly so the upslope will not be deep
and snow should be light. Snow will continue over the c mountains with
snow finally decreasing over the SW mountains snow should end over the
plains late in the day on Wednesday. If the ec model is correct...the snow
may end earlier.

Thursday into the weekend...

Dry conditions return. We should see temperatures at or above 40f for maxes over
the plains Thursday...and 50s Friday and Sat. This dry and mild pattern will
likely continue through middle week next week. \/Hodanish

&&

Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 252 PM MST Sat Feb 28 2015

For the three main taf sites of kcos...kpub and kals...clouds are on
the increase from the SW and light snow is expected to return and
continue this evening. Moderate to heavy snow is forecast for the higher
terrain through the period...especially the southern mts and the
Continental Divide. Look for MVFR to IFR conditions due to occasional snow...fog and
lowering clouds to develop at kcos and kpub between 23z and 02z
this afternoon...and to persist at all three sites through 12z tomorrow
morning. Activity will taper off...then pick up again by 21z Sunday
afternoon.

&&

Pub watches/warnings/advisories...
Winter Storm Warning until 5 PM MST Monday for coz058-060-061-
066>068-073-075.

Winter Weather Advisory until 5 PM MST Monday for coz059-064-065-
074.

&&

$$

Short term...Moore
long term...hodanish
aviation...Moore

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