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Area forecast discussion 
National Weather Service Pueblo Colorado
1120 PM MDT Tuesday Sep 1 2015

issued at 532 PM MDT Tuesday Sep 1 2015

Updated grids/zones mainly for probability of precipitation and sky cover...based on
the latest radar...Sat...and observation as well as high res model data.
Should see convection wind down over the next few hours. Rose


Short term...(this evening through wednesday)
issued at 239 PM MDT Tuesday Sep 1 2015

Currently...isolated to scattered showers and thunderstorms have
developed over the mountains early this afternoon while a couple of
isolated cells have formed over eastern Las Animas County.
Elsewhere middle and high level clouds have spread across the region.
Temperatures have been warm with 80s to 90s across the lower

Tonight...models in good agreement with a weak disturbance working
northeast out of The Four Corners region late this afternoon and
evening in persistent southwest flow. Expect increasing shower and
thunderstorm coverage...initially over the mountains...and spreading
into the I-25 corridor this evening...before shifting east and
dissipating after sunset. The main threats from thunderstorms will
be lightning...gusty outflow winds and locally heavy rainfall. A
few cores...especially south along the New Mexico border will be
capable of producing half inch in diameter hail. Precipitation
should come to an end late tonight with dry conditions across the
region heading into Wednesday morning.

Wednesday...southwesterly flow aloft will continue across Colorado.
Current model analysis indicates the next disturbance will be
working its way north out of New Mexico...but will be too far
southwest to have much impact on the area. Models develop afternoon
and evening showers and thunderstorms over the mountains. The best
coverage looks to be along the Continental Divide...with more
isolated coverage over the eastern mountains. One or two cells may
be able to make it off the higher terrain and into the Palmer Divide
and Raton Mesa during the late afternoon hours...while the remainder
of the plains remains dry. Temperatures will once again be hot
across the region with 80s and 90s for afternoon highs. Mozley

Long term...(wednesday night through tuesday)
issued at 239 PM MDT Tuesday Sep 1 2015

Any lingering convection Wednesday evening will end quickly most areas with
lack of much upper support...although a few -shra/-tsra may
redevelop over the San Juans toward Thursday morning as deeper moisture
begins to spread northward into southwestern Colorado. Models continue
to trend faster with the surge of deep moisture coming out of the
southwest Thu/Fri...with fairly widespread convection looking
possible across the mountains both days. Still appears higher
terrain/interior valleys from the sangres westward will see the
best chance of rain this period...with potential for some heavy
rainfall along the Continental Divide. Eastern slopes and
southeast plains will see less in the way of activity as low and
middle level flow keep a downslope westerly component. Maximum temperatures
will remain little changed on Thursday...then drift downward a few
degrees over mainly the mts on Friday as clouds and moisture move

Upper trough over the Pacific northwest deepens Sat then moves
into the northern rockies sun...with middle level flow gradually becoming
more west-SW through the period. Enough moisture lingers Sat for
isolated to scattered convection from i25 westward...before flow
becomes fairly strong westerly on sun...leading to a mostly dry
day all areas. Maximum temperatures both days perhaps a degree or two cooler
than Friday many locations as heights begin to fall slight with
flattening of the upper ridge. Still appears cold front will drop
south through Colorado late sun/early Monday as upper trough
continues to March eastward across the northern plains. GFS is
much more moist then Euro both Monday and Tuesday...with low level
upslope and middle level moisture combining for fairly widespread
precipitation both days. Euro has some weak upslope Monday into Tuesday...but
keeps deeper moisture and most precipitation well south of the area in
nm/TX/OK. Extended procedure gave isolated to low scattered probability of precipitation
most locations both days which will be fine for now. Maximum temperatures
continue to drift slowly downward following the frontal
passage...with maxes back toward seasonal normals many areas
Monday...then little change on Tuesday.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 1102 PM MDT Tuesday Sep 1 2015

Monsoon flow will remain over flight area next 24 hours although
tomorrow looks a little drier overall than it was today. Storm
coverage should be less especially on the plains. Generally VFR
across flight area although MVFR/IFR/LIFR conditions can be
encountered in areas of precipitation. General window for
convection Wednesday will be 18z-06z...with convection most
widespread and intense 21z-03z...mainly over the mountains.

Kcos and kpub taf sites likely to remain VFR next 24 hours...with
convective chances mainly west of both sites...and too low to put
in terminal forecasts. Kals also likely to remain VFR next 24
hours although thunderstorms in the vicinity will be possible there after about 21z
Wednesday. There is an outside chance that conditions could go
down briefly to MVFR/IFR/LIFR in precipitation but chance is very
slight and too low to put in terminal thunderstorms in the vicinity starting
21z will suffice for now.


Pub watches/warnings/advisories...


short term...mozley
long term...petersen

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