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Area forecast discussion 
National Weather Service Pueblo Colorado
423 am MST Friday Jan 30 2015

Short term...(today and tonight)
issued at 358 am MST Friday Jan 30 2015

Currently...an upper low located over Southern California was drawing
abundant moisture up across Arizona and nm...and producing cloudy skies
for Colorado. Light snow was being reported along the Continental Divide and San Luis
valley this morning...while the cloud cover has kept temperatures hovering
right around 30f for most locations as of 4 am.

Today and tonight...models indicate that the upper low over Southern
California this morning will move very little over the next 24 hours. This
will keep much of the focus for precipitation across Arizona...nm and the extreme
southern portions of Colorado. S-SW surface winds through much of the day will
help to warm the plains to around 50f...so any precipitation that falls there
through the day will be liquid. Therefore...as the models have been
trending to the past day or so...the area that will most likely see
the highest amounts for new snowfall will be the SW mts...and to a
lesser degree the S sangres. Ongoing highlights look fine at this
time though the northernmost areas are a little questionable...but
will keep things as is for now. Surface cold front is forecast to drop
south of the Palmer dvd very early Sat morning...so min temperatures should
drop down into the 20s after midnight. Moore

Long term...(saturday through thursday)
issued at 358 am MST Friday Jan 30 2015

..continued unsettled through Saturday...Drying out for Sunday...

Models in fairly good agreement with synoptic scale features through
Sunday...with the upper low dropping into southern Arizona/northwest old
Mexico...while a shortwave trough within the northern stream drops
through the northern U.S rockies and across northeast Colorado Sat
night/early Sunday. This puts southern Colorado in between the
systems...with shortwave energy ejecting to the northeast out
ahead of the closed low across southern Colorado on Saturday. Initially
snowfall on Saturday looks mainly confined to the mountain areas
until a cold front drops in from the north Saturday
night...potentially enhancing snowfall for the southeast plains.
Its this latter detail that the models are in disagreement on.
Nam12 is heavier with potential snowfall for the southeast plains
(1-3") Sat afternoon through Saturday night...where as GFS and
European model (ecmwf) depict much lighter amounts. Confidence is rather low at
this point...as majority of the energy from the northern stream
will track to the northeast of the forecast area...while energy
ejecting to the northeast ahead of the closed low is rather weak
and nondescript. Think it going to come down to timing of both of
these features and whether they can act together to enhance
precipitation for southern portions of the forecast area Saturday
evening. For now...have sided with the lighter quantitative precipitation forecast amounts of the
GFS/ECMWF...but will have to watch closely how these details
evolve for the Saturday evening period. Meanwhile...advisories for
the mountain areas still look warranted through Saturday evening
with continuous light snow expected.

Sunday will dry out...but will also be colder behind the front with
brisk north winds across the southeast plains through the day.

Northwest flow remains over the area through the majority of the
extended...with periodic shortwaves embedded within the flow
bringing snow showers to the central mountains at times. Lee
troffing will bring breezy west winds and above normal temperatures
to the region for Monday and Tuesday. Another cold front may drop
into southeast Colorado for Wednesday though there is some uncertainty
with this as 06z GFS has trended more towards the European model (ecmwf) in keeping
the colder air farther north until perhaps Wednesday night. Will
keep probability of precipitation in the silent category for now. Eventually another ridge
builds over the West Coast and translates eastward towards The
Rockies for Friday...so expect dry and warmer weather to spread in
for late week into next weekend. -Kt

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 358 am MST Friday Jan 30 2015

Kals...MVFR to IFR conditions due to light snow and low cloud deck
over the next 24 hours.

Kcos and kpub...VFR conditions through the day...then lowering ceilings
with isolated precipitation leading to possible MVFR conditions for kcos
after 23z...and after 01z for kpub.

&&

Pub watches/warnings/advisories...
Winter Weather Advisory from 8 am this morning to 8 PM MST
Saturday for coz058-060-061-066>068-073>075.

&&

$$

Short term...Moore
long term...knots
aviation...Moore

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