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Area forecast discussion 
National Weather Service Pueblo Colorado
321 PM MST Friday Nov 27 2015

Short term...(this evening through saturday)
issued at 319 PM MST Friday Nov 27 2015

..some areas of light snow tonight...
..Cold but less snow tomorrow...

The models are not doing very well today in capturing bl processes
and the cloud/precipitation potential across the County Warning Area. Relatively shallow
cold air and southeasterly flow across El Paso County has lead to light snow
through today...albeit with little accumulation...while the rest of
the plains have stayed generally precip-free. Meanwhile...the San
Luis valley has seen a good amount of sun...despite deep saturated
layers prognosticated by the models. So...the short term forecast is a bit
problematic and persistence will rule for now.

Tonight...another wave of light snow showers is likely as the low
pressure system over northwest Arizona/SW Utah ejects to the NE into Wyoming by Sat
afternoon. Best forcing from this disturbance will be this best chance of additional accumulating snow will be from
now through about 06z tonight. Most accums should be on the light
side...under an inch. The San Juans will continue to see steady
light to MDT snow so will continue the advisory for that area.
Another area that might see some respectable accums is the Arkansas
River Canyon along with Fremont County....the northern sangres...and the
Wet Mountain Valley. High res models like the hrrr are showing the best
evening potential in that region...with several inches of snow
possible by Saturday morning. Still pretty uncertain where exactly
the highest accums will be...or whether this heavier band of snow
develops at will keep headline-free for now. Will have to
keep a close watch on how things develop this evening. In
general...suspect the models are overdoing precipitation potential through
Sat morning so have cut back quantitative precipitation forecast accordingly. Have added some
areas of pc fzdz over the eastern plains into Sat model
sounding indicate some potential for additional light fzdz in the
shallow cold air mass.

Saturday...conditions should improve somewhat but it will continue
to be cold...with temperatures on the plains struggling to hit 30 degrees.
Warmest spots will be the middle elevation areas close to the wets and
southern sangres...depending on how deep the cold air is. The San Luis
valley should also get above freezing for much of the afternoon. Will
keep very low probability of precipitation in for the area tomorrow afternoon. The GFS
continues to show some light quantitative precipitation forecast over southeast Colorado...while the NAM is
showing dry conditions. With the upper low still to our northwest there
will still be some modest forcing and moisture for precipitation...but
chances for measurable precipitation do not look very high...and the more
likely scenario is for some clearing by Sat afternoon. Rose

Long term...(saturday night through friday)
issued at 319 PM MST Friday Nov 27 2015

Sat night the upper low is expected to be around the extreme southwestern
corner of Wyoming. Forecast models are generally dry...but do show the
potential for some light snow...but portions of the far southeastern
plains could see some patchy fzdz as well. Most locations should
see lows in the teens.

On sun the upper low center is forecast to move into central Wyoming. A
disturbance in the flow around the southern side of the expected
to move into western Colorado...enhancing snow chances along the Continental Divide and
maybe into the Teller County and Pikes Peak area in the afternoon.
Across the southeastern plains and mountains there will continue to be the possibility
of some light snow...with some patchy fzdz still possible in areas
near the Kansas border. High temperatures on sun are expected to be in the 30s
over most of the lower elevation locations.

Sun evening the upper trough and disturbance move across the forecast
area...likely bringing a better chance for snow to the eastern mountains
and plains. At this time any snow accumulations are expected to be
light. By late night/early Monday morning the disturbance is expected
to move east of the area and with the precipitation lifting northeastward. The
NAM is a little faster ending the precipitation from west to east than the

On Monday the upper low is expected to move into the eastern half of
NE...leaving west to northwest flow aloft over the forecast area...along with
drier conditions. Moisture in the northwest flow will likely keep some light
snowfall going over the central mountains on Monday. Highs on Monday may get
into the lower 40s over some of the southeastern plains...but the rest of the
lower elevations should mainly be in the 30s.

Tuesday through Friday dry weather is expected with high temperatures warming a little
each day...with highs by Friday being in the 50s over the southeastern plains
and in the 40s over the High Valley areas.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 319 PM MST Friday Nov 27 2015

Periods of light shsn will continue to be possible through about 06-
08z another disturbance moves through northern Colorado. MVFR to
occasionally IFR conditions will be possible with the precipitation. Some
fog can not be ruled out early Sat morning...especially at kals...but
will keep kals VFR for now. Some model guidance is predicting low
ceilings to continue through Sat afternoon at kpub and especially
kcos...but the more likely scenario is for VFR conditions at least
by Sat afternoon. With continued southeasterly surface winds...there is still a
significant possibility that kcos especially could remain MVFR to
IFR with low ceilings. Rose


Pub watches/warnings/advisories...
Winter Weather Advisory until 5 PM MST Saturday for coz067-068.



Short term...rose
long term...28

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