Area Forecast Discussion
Issued by NWS Pueblo, CO

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

FXUS65 KPUB 120502

Area Forecast Discussion
National Weather Service Pueblo CO
1002 PM MST Thu Jan 11 2018

.SHORT TERM...(This evening through Friday)
Issued at 318 PM MST Thu Jan 11 2018

...Snow returns to the Central Mountains Friday, while the plains
become windy and warmer...

NW flow aloft managing to wring out a few flurries over the Central
Mountains this afternoon, while the remainder of the region has been
dry and seasonably cool. Overnight, strengthening upward motion
ahead of the next nwly flow short wave will reach the Continental
Divide after midnight, with snowfall gradually increasing in
intensity from Cottonwood Pass northward through sunrise. Farther
east, W-SW winds will begin to stir as lee surface trough deepens,
keeping temps up slightly along and east of the mountains, while
colder air settles in the valleys and lower elevations of the
eastern plains. On Fri, upper wave crosses the state, with window
for best lift in the morning across the Central Mountains. Should be
enough snow and wind for a low end advisory over the higher peaks
(zones 58/60), where a 4-8 inch storm total will be possible by late
afternoon. Suppose we could see some virga elsewhere across the area
as wave passes, though won`t mention in the wx grids as better
forcing should stay north and east. Winds will turn NW and increase
through the day across most of the region, with gusts in the 30-40
mph range over the eastern mountains and plains by afternoon.
Despite some weak mid level cold advection, max temps Fri afternoon
will be much warmer under deep mixing, as bulk of surface cold air
lurks just NE of the area until evening.

.LONG TERM...(Friday night through Thursday)
Issued at 318 PM MST Thu Jan 11 2018

Friday night-Sunday...Models remain consistent with moderating
northwest flow aloft across the region through the period, as
Friday`s embedded short wave continues to translate south and east
into the High Plains. Passing wave sends a backdoor cold front
across the eastern plains, with a shallow cold airmass spreading
west across southeast Colorado Friday night. Models continue to keep
the coldest air associated with this system well east of the area,
however, with weak easterly upslope, will likely see some stratus
developing across the lower Arkansas River Valley into Saturday
morning, though still does not look to make it into the I-25
Corridor at this time. Cool upslope flow to continue Saturday, with
dry weather expected and highs mainly in the 40s across the lower
elevations, and in the 20s and 30s across the higher terrain. Lee
troughing develops across the I-25 Corridor Saturday evening, with
the the shallow cool airmass spreading east overnight and looks to
mix out completely across the eastern plains on Sunday, owning to
highs warming back into the 50s across the lower elevations on
Sunday and mainly in the 30s and 40s across the higher terrain.

Sunday night-Tuesday...Latest models agree on another stronger wave
embedded within the northwest flow aloft will move across the
region, though differ on timing and western extent of this passing
system. The EC remains the fastest and furthest west, brining a
colder airmass into eastern Colorado later Sunday night, where as
the GFS is only slightly later with bringing another backdoor front
across the area later Monday morning, though keeps the bulk of the
colder airmass in Western and Central Kansas. The colder and further
west EC solution would bring better chances of low clouds and fog
across southeastern Colorado, along with possible light freezing
drizzle or flurries Sunday night and Monday, whereas the GFS
solution would tend to keep any precipitation chances east of the
area. At any rate, have stayed with blended model silent pops for
the plains into Monday, though have gone closer to the cool side of
guidance for temperatures, with highs in the 30s and 40s areawide on
Monday, coolest across the far southeast plains, with dry weather
and slight warming across southeast Colorado for Tuesday.

Wednesday-Thursday...Some differences in the extended portion of the
forecast, with the EC bringing another embedded shortwave across the
area Wednesday afternoon and evening, while the GFS is weaker and
much further east with the system. To far out in time to tell and
stayed with a dry forecast and temperatures warming back to at and
slightly above seasonal levels.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 947 PM MST Thu Jan 11 2018

Increasingly moist northwest flow will spread snow and areas of
blowing snow back into the central and northern Colorado mountains
along the Continental Divide tonight through Friday. Areas of
MVFR to LIFR conditions can be expected with this activity from
the northwest slopes of the La Garitas northward along the Sawatch
Range through Friday. Elsewhere, generally VFR expected, though
there could be a spotty MVFR rain or snow shower. The KCOS, KPUB
and KALS terminals should generally see VFR conditions over the
next 24 hours. However, some shallow, patchy ground fog could
occur around the KALS terminal late tonight due to recent spotty


Winter Weather Advisory until 5 PM MST Friday for COZ058-060.



AVIATION...LW is the U.S. government's official web portal to all federal, state and local government web resources and services.