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fxus65 kpub 171709 

Area forecast discussion
National Weather Service Pueblo Colorado
1009 am MST sun Nov 17 2019

Short term...(today and tonight)
issued at 347 am MST sun Nov 17 2019

Currently...the upper trough was exiting east into the central part
of the US, leaving brisk northwest flow aloft across Colorado. There
were some areas of low clouds across the plains this morning as of 4
am. Temps have cooled into the 20s and 30s for most areas, though
around 40f was still being reported at klhx and klaa as of 4 am,
while the center of the San Luis valley had cooled into the 10-15
degree range.

Today and tonight...northwest flow aloft will remain across the
state through the short term. Patchy cloud cover this morning for
the plains is expected to clear between 10 am and noon, though there
still will be some Mt top clouds through the aftn, especially over
the central mts and northward. Maximum temps this aftn are forecast
to be seasonal, warming into the 50s for most locations. Tonight
lows will drop into the upper 20s to mid 30s for most locations,
though areas right along the eastern slopes should stay in the upper
30s while the San Luis valley drops into the teens to mid 20s.

Long term...(monday through saturday)
issued at 347 am MST sun Nov 17 2019

Temperatures rebound for Monday and Tuesday as northwest flow
aloft transitions to southwesterly ahead of the next developing
West Coast system. Lee side surface trough deepens especially
Tuesday, with 700 mb temperatures warming to +7 to +9c over most of
southern Colorado. This should yield temperatures in the 70s across the
plains...with 60s valleys and 40s and 50s across the mountains.
Record highs for Tuesday seem safe for now (cos 76 in
82 in 2007...and als 68 in 2007) high level wave cloudiness
may keep temperatures below these values...but will need to watch
this day closely. There could also be some spotty near critical
fire weather conditions along the I-25 corridor where westerly
winds will funnel through the gaps and river valleys (ex:
Walsenburg and Canon city) causing breezy conditions during the
afternoon. For now, conditions look too spotty and coverage too
sparse to warrant fire weather highlights.

Extended range models still eject remnants of the weakening upper
low off the coast of baja across Colorado on Wednesday ahead of a new
intensifying upper low which develops across Southern California. Extended
models have come into better agreement gradually lifting this
upper low across Utah/Arizona by Thursday before ejecting it eastward
across Colorado/nrn nm on Friday at varying speeds. Ec is the slowest,
holding the upper low back across Colorado by 00z Sat. Canadian and GFS
push the system eastward into western or eastern Kansas respectively by
this same time frame. So there are still some uncertainties

For sensible weather, will see lower elevation rain and higher
elevation snow showers spread across southern Colorado on
Wednesday with the leading wave ejecting across southern Colorado during
the day. Temperatures are still relatively warm on Wednesday even
though a cold front will moving through the plains behind the
passing northern stream upper trof. A period of upglide develops
as the upper wave moves across which will spread rain showers
across the plains during the day. Activity should decrease
Wednesday night as this initial wave lifts off to the northeast.
Areas most likely to receive beneficial snowfall will be the
Southwest Mountains and southern Sangre de Cristo Mountains as
southwest flow will provide favorable orographics for these areas
(especially eastern san juans). Model consensus suggests several
inches of snow for the Southwest Mountains and to a lesser extent
the higher elevations of the sangres. These areas may need some
winter weather highlights as this time frame approaches and
details become more clear. A bit of a lull in precipitation for
Wednesday evening then more rounds of higher elevation snow
showers and lower elevation mixed rain and snow showers persist
for Wednesday night through Friday as the upper low approaches
providing continued southwesterly moisture fetch/orographics for
the Southwest Mountains, and isentropic upglide/upper difluence.
Overall the Southwest Mountains should fair best with this storm,
with some moderate to even heavy snowfall. System opens up as it
tracks across Colorado through late week, so southeast mountains and
plains will see rounds of showers at times with a mix or change
over to snow each night as temperatures drop below freezing. But
overall, system doesn't look all that cold or wrapped up to
produce a heavy precipitation event for the southeast mountains
and plains. But certainly some rounds of beneficial precipitation
will be possible.

Overall extended forecast leans towards model blends with timing
challenges as the system ejects across Colorado late week. This will
keep cooler and unsettled weather through early Saturday before
drier weather returns for Sunday again. -Kt


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1008 am MST sun Nov 17 2019

VFR conditions at all three terminals through the next 24 hours
with generally light winds and passing mid to high level clouds,
especially tonight. Mozley


Pub watches/warnings/advisories...


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