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fxus65 kpub 300529 

Area forecast discussion
National Weather Service Pueblo Colorado
1129 PM MDT Wed Mar 29 2017

Short term...(this evening through thursday)
issued at 244 PM MDT Wed Mar 29 2017

Upper low is pulling away to the east across central Kansas with
area of wrap around precipitation across the far southeast Colorado plains
quickly coming to an end this afternoon. There could be an isolated
instability shower on the back side of the system for a few more
hours late this afternoon through early evening across the southeast
plains. Otherwise, precipitation should be done. With clearing
skies overnight...temperatures should end up around freezing for
most areas across the plains...with a range of teens and 20s for the
higher mountains and cold trapping valleys. There could be some
patchy fog tonight...especially along the river valleys as dew
points will remain high from the recent precipitation.

Temperatures will recover nicely for all areas tomorrow. Lee trof
redevelops across the plains late tonight with southerly flow
increasing on Thursday. This should help temperatures warm back
into the mid to upper 60s for the plains, 50s and lower 60s for the
valleys, and 30s-40s for the mountains. Southwest flow aloft will
increase ahead of the next closed low dropping through Nevada/western Utah
late in the day. This will pick up some moisture and generate some
rain and snow showers across the Continental Divide late in the day.
Elsewhere will remain dry until the next storm heads in. -Kt

Long term...(thursday night through wednesday)
issued at 244 PM MDT Wed Mar 29 2017 storm to arrive Friday afternoon...

Models continue to agree that the weather pattern will remain
active. A very strong storm system is forecast to impact the
region beginning Friday, clearing the area on Sunday. Models both
agree that another storm system will impact the area Monday into
Tuesday, but there large spreads in storm track and strength,
therefore less confidence in the expected outcome.

Thursday night through Sunday...a very strong upper level storm
system is forecast to move across the region during this period.
Flow will increase out of the southwest Thursday night with
scattered showers over the higher elevations of the Continental
Divide. Snow will be confined initially to above 9 kft Thursday

The upper level low is forecast to drop south out of Utah and then
east across Arizona and New Mexico, before ejecting northeast on
Sunday. This is a very favorable storm track for all of southern
Colorado to see widespread moderate to heavy precipitation. This
storm track will bring deep upslope flow, through 500 mb, to
southern Colorado. In addition, multiple disturbances are forecast
to wrap around the storm out of New Mexico, with each disturbance
bringing enhanced precipitation to the region. Strong lift due to
the upper storm along with orographic upslope flow will provide a
focus for heavier precipitation over the Palmer Divide, south
along the eastern mountains, and into the I-25 corridor Friday
into Saturday. The heaviest precipitation is expected from late
Friday afternoon, through Saturday morning. How much snow falls
will be highly dependent on the rain-snow line. Current model
solutions are slightly colder than the previous two storms. Heavy
snow will likely be confined to the central and eastern mountains
Friday afternoon into the evening, spreading into the Palmer
Divide later Friday night. Snow levels will initially start out
about 9 kft, dropping through the evening hours to near 5 kft
overnight. Current snowfall projections put 1 to 3 feet of snow in
the eastern mountains. Snowfall over the Palmer Divide may range
in the 8 to 15 inch range, while Colorado Springs may see a couple
of inches through Saturday morning. By Saturday afternoon and
evening, the main precipitation band will shift south over the
southern I-25 corridor and slowly lift east across the plains by
Sunday morning.

These snow totals are just preliminary at this time, and will
depend highly on the exact storm track and where the rain-snow
line will fall. Rainfall amounts may once again be pretty
impressive with 1 to 2 inches of liquid expected below the rain-
snow line. In addition, a few thunderstorms may be possible Friday
afternoon from Colorado Springs, southeast to near Springfield.
Cape values around 700 j/kg and a low level boundary across the
plains may provide an enhanced focus for thunderstorm development.

Monday through Wednesday...the next upper level storm system is
forecast to move into the region by Monday, before exiting the
area Wednesday morning. There are big differences between the GFS
and European model (ecmwf) as far as storm track. The GFS is much further north
with the upper low track which would limit precipitation chances
across southern Colorado. The European model (ecmwf) is much more favorable for
another round of mountain snowfall and decent precipitation
amounts across the plains, especially Monday night into Tuesday.


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1127 PM MDT Wed Mar 29 2017

VFR conditions expected across the forecast area over the next 24
hrs, including the three main taf sites of kcos, kpub and kals.
Winds across the area will start showing an increase of 10-15 kts
from generally a southerly direction starting this aftn as the
next approaching system digs south across the Great Basin. Moore


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