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fxus65 kpub 091716 

Area forecast discussion
National Weather Service Pueblo Colorado
1016 am MST Mon Dec 9 2019

issued at 741 am MST Mon Dec 9 2019

Update for expiration of the Winter Weather Advisory for the
central mts. Incorporated latest obs data.


Short term...(today and tonight)
issued at 340 am MST Mon Dec 9 2019

Currently...the trough axis of the storm system was slowly tracking
east-southeast across the region, still producing some snow over
the higher terrain but weakening in intensity. A cold front pushed
south across the eastern plains overnight, but as of 4 am the front
had not made it to Walsenburg quite yet. Temps have fallen into the
30s and 40s for the plains, and 20s for the high valleys.

Today and tonight...the storm system looks to be on track for
continuing to sweep east across the forecast area through the day,
then exiting the state by this evening. Intermittent snow will
continue over the higher terrain through the day, with some snow
expected to develop over the Raton Mesa and southern border this
afternoon. Otherwise, snow has decreased greatly over the SW mts
and decided to drop the warning there early. The advisory for the
central mts will continue until the previously scheduled 8 am end
time. Brisk and at times gusty winds this morning in spots will
persist until midafternoon before diminishing, but west to
northwest winds aloft for the higher terrain will remain gusty
well into this evening. The frontal passage overnight has ushered
in cooler air, and highs today are forecast to remain in the 30s
to lower 40s. Tonight, clearing skies will aid in efficient
radiational cooling with expected overnight lows in the teens for
the plains and single digits for the high valleys. Moore

Long term...(tuesday through sunday)
issued at 340 am MST Mon Dec 9 2019

Dry and mild weather returns for mid week as northwest flow on
Tuesday gets replaced by ridging followed by southwest flow ahead of
the next progressive storm system. Low temperatures Tuesday night
will be quite cold across the interior valleys with guidance
suggesting lows around 0 or even negative values for kals, and
likely the upper Rio Grande Valley as well. Have dropped min
temperatures accordingly. By Wednesday, increasing high cloudiness
ahead of the next upper trough will be spreading in. Lee troughing
and 700 mb temperatures around 0 to +2c should keep mild temperatures in
place along the I-25 corridor and far eastern plains where southerly
winds will increase, promoting deep mixing. Thickening mid/high
cloudiness however could serve to cut back temperatures a bit where
winds don't kick up...which could occur across Pueblo, Crowley, and
Otero counties.

Models diverge with the track of the upper trof for Wednesday night
and Thursday with ec and Canadian closing off southern stream energy
across Arizona and dropping it southeastward into northern old Mexico and
West Texas on Thursday. GFS and nam12 keep system much more progressive
and farther north with the upper trof moving from the 4 corners
region into the Texas/OK Panhandle by mid day Thursday. GFS ensemble
mean gives a nod to the ec/Canadian solutions with its more
amplified southern stream energy, and several members look
similar to the farther south/closed off solution. In spite of the
differences in the storm track, models are pretty dry with this
system, with ec suggesting a warmer day for Thursday vs GFS. Have
stuck close to model blends for now given the uncertainties.

Next round of persistent snow spreads into the mountains Thursday
night as a nearly zonal Pacific jet drives moisture into the
Continental Divide region. Precipitation will spread eastward at
times Friday through Sunday as embedded impulses and overrunning
over a cold front sets up across the plains. Best chance for
precipitation on the plains appears to be Sunday/Sunday night as the
upper trough moves across the region. Could see some moderate to
heavy snow accumulations through this 3 day period along the
Continental Divide...with some light snowfall accumulations across
the adjacent plains Saturday night and again Sunday night. Overall,
this storm system doesn't look that cold for the plains, so snow
accumulations may end up confined mainly to the Palmer and Raton
Mesa regions with a light snow or rain/snow mix across the plains
during the overnight/early morning hours. System shifts east of the
area for Monday with dry weather returning. -Kt


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1016 am MST Mon Dec 9 2019

VFR conditions are anticipated throughout the forecast period for
kals, kcos, and kpub. There are low clouds filling over kcos and
kpub currently, and the forecast is for those clouds to be
reinforced by east-southeasterly winds during the afternoon. Kpub
will likely see scattered to few cloud, whereas kcos will see broken to
overcast clouds. Kcos is the most likely location to have MVFR
conditions form. Kals will have a persistent cloud deck overhead
during the day, but should remain VFR.


Pub watches/warnings/advisories...


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