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Area forecast discussion 
National Weather Service Pueblo Colorado
1151 PM MDT Sat Sep 20 2014

issued at 1117 PM MDT Sat Sep 20 2014

Made adjustments to the current shower and thunderstorms potential
based on the latest radar and high-res model trends. Thunderstorms
are beginning to develop over Huerfano and southern Pueblo
counties where the 00z NSSL WRF and hrrr runs are indicating it
will Blossom overnight. For the most part have kept the best
chances for showers and thunderstorms over the eastern mountains
into the I-25 corridor. Have limited areas of the far eastern
plains which continue to come in drier with each high res model
run. Mozley

Update issued at 852 PM MDT Sat Sep 20 2014

Updated to make a few adjustments for showers and thunderstorms
across the plains through midnight. Current radar analysis shows
shower and thunderstorm activity from the Continental
Divide...northeast across Teller and El Paso counties. These
storms have been very slow moving...and the stronger cells are
putting down between one half and one inch of rainfall. If
stronger cells move over burn scars...they could produce flash
flooding and this will need to be monitored. As far as the
plains...the high res models still developing an area of showers
and thunderstorms around midnight along the eastern mountains and
spreading east through Sunday morning. Mozley


Short term...(this evening through sunday)
issued at 245 PM MDT Sat Sep 20 2014

Currently...the upper ridge of high pressure remained across the
region...while a closed upper low was located over the central California
coast. This pattern was drawing moisture up into the desert
SW...with a good amount of convection firing over Nevada and southern Utah
as of 3 PM. Across the County Warning Area...surface observation throughout the morning have
shown a frontal boundary pushing through the plains producing gusty
NE-southeast winds at times...but with little other effect. Temperatures this afternoon
have been about the same as have been recorded the past two days.

Tonight and tomorrow...over the next 24 hours...models indicate that
the ridge presently over the region will start to weaken...while the
upper low over California moves inland and tracks to the NE into central Nevada.
Moisture advection into western Colorado is expected to strengthen as the
low approaches...but the real story for the short term is the
continued persistent easterly surface flow that is forecast for the east
plains and mts tonight through tomorrow. Though there has been a
very slow start to any sort of precipitation over the mts...all the models
are still hanging onto the Promise of showers and isolated storms
over the mts moving off across El Paso County by 02z...then across
Pueblo County and areas east between 06z and 09z. This low level flow
will kept isolated probability of precipitation all areas east while the mts
and western areas get increased probability of precipitation to reflect the increasing
incoming moisture. Models do indicate that tomorrow will be the
first break in the above normal readings are forecast to
warm into the 70s in the afternoon. Moore

Long term...(sunday night through saturday)
issued at 245 PM MDT Sat Sep 20 2014

A few strong thunderstorms will be possible at the beginning of
this a trough aloft moves across the region
combines with some instability and favorable shear. At this time
the most favorable parameters appear to favoring the greater I-25
corridor region. Storm Prediction Center has area mentioned for enhanced convection
for this day.

Tuesday will likely be dry across the forecast area. Northwest flow
will advect drier air aloft into the region...although some
residual level moisture will still be around...especially over the
far east plains.

Wednesday...a weak boundary is forecast to move down the plains this
day. This boundary will stall down along the Raton Mesa...and this
area...along with the S where the best chance of precipitation
will be on this day. Precipitation will likely be low end scattered at
best...mainly in the vicinity of the S sangres.

Thursday...models diverge significantly on this day. GFS drops a
cutoff 500 mb low across c Nebraska while ec has weak SW flow over
the region. Obviously...if the GFS is correct it will be cooler
over the region then the ec. For now leaned heavily towards the ec
guidance...keeping temperatures up into the 70s and 80s across the

Friday...not much change in the expected....a deep trough moving
onshore across calif will be gradually moving towards the region.
However...trough is still far enough to the west...and middle level
flow will remain weakly from the SW. This will keep temperatures mild
with only isolated probability of precipitation at best.

Overall...temperatures during this period will remain above normal with
maximum temperatures in the l/m80s across the plains. These temperatures are about 4
to 7f above normal for this time of the year. Except for
Tuesday...precipitation chances will be low. We are significantly below
normal for precipitation over the region for the month of
September....and have been this way since about middle August across
the region (see temperature/precipitation monthly climatology charts on the bottom of
National Weather Service Pueblo webpage for specific numbers). \/Hodanish


Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1117 PM MDT Sat Sep 20 2014

Kals...showers are passing across the San Luis valley and will do
so through Sunday morning with lowered ceilings to around 1000 feet.
There will be a slight improvement with ceilings Sunday afternoon with
afternoon thunderstorms possible.

Kcos...showers and thunderstorms are moving around the El Paso
County area and will continue through Sunday morning. The latest
models have trended south...with most of the activity across
Pueblo County. Southeast winds should help produce low ceilings and
possibly fog through Sunday morning. There will be some
improvement Sunday afternoon with stratus decks around 2-5 kft.

Kpub...models indicating shower and thunderstorm development by
07z with lowered ceilings and visible due to storms moving across the area
through Sunday morning. There will be improvements middle Sunday
morning with stratus through the afternoon running around 3-6 kft.


Pub watches/warnings/advisories...


short term...Moore
long term...hodanish

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