Area Forecast Discussion
Issued by NWS Pueblo, CO

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FXUS65 KPUB 181015

Area Forecast Discussion
National Weather Service Pueblo CO
415 AM MDT Thu Jul 18 2024


- Scattered afternoon and evening showers and thunderstorms,
  some strong to severe, especially along and east of the I-25

- Below normal temperatures and continued chances for daily
  showers and thunderstorms dominate the extended forecast.


Issued at 413 AM MDT Thu Jul 18 2024

Shower and thunderstorm development still ongoing across the
southeast plains early this morning, as mid level energy continues
to move through the region. These storms have been steadily dropping
south during the overnight hours, and expect that to continue over
the next couple of hours as this development follows the instability
axis south. At this point, would expect brief heavy downpours and
small hail with any stronger storm, before these storms exit. A
moist air mass is in place early this morning, and this can be seen
with the expansive low stratus which has developed just lee of the
southeast mountains. South to southeast low to mid level flow has
been in place most of the night and supporting this development, and
while I think these clouds will remain during the early morning
hours, should see a scattering trend as 700mb flow continues to veer
more westerly. Overall a clearing trend over much of southern
Colorado this morning, with slightly warmer temps expected today
owing to some rising heights aloft.

Another day of shower and thunderstorm development is expected over
much of southern Colorado today, as well as the risk of scattered
strong to severe storms along and east of the I-25 corridor. While
some ridging will be noted today, the region will still be on the
fringe of this ridge. This should allow additional short wave energy
to drop south today. Will once again see low level flow
strengthening out of the east today, along with 700mb flow turning
back to the east southeast. This large scale support, moist upslope
flow, and lee troughing will support shower and thunderstorm
development over and near the higher terrain by early afternoon. By
mid to late afternoon, should see this development spread east
across the I-25 corridor and then continue into the eastern plains
through the evening hours.

Moist and unstable conditions are already in place early this
morning, with surface dew points in the upper 50s to around 60
degrees up to the I-25 corridor and dew points in the upper 40s to
around 50 degrees in parts of the mountains and mountain valleys.
While day time mixing should help to bring down this moisture,
mainly over/near the higher terrain, the strengthening easterlies
will help to offset this. This will help support MLCAPE values of
500 to 1000 j/kg over and just lee of the southeast mountains, with
instability once again increasing to the east across the plains.
Think values will easily approach 2000 j/kg across the plains this
afternoon and evening. Also, setup today will once again support
modest bulk shear values. Given all of this, think scattered strong
to severe storms capable of producing hail up to the size of ping
pongs, wind gusts up to 65 mph, and heavy downpours. Will also need
to keep an eye on area burn scars later this afternoon and evening,
as a few stronger storms could move across these areas.


Issued at 413 AM MDT Thu Jul 18 2024


Northwesterly to northerly flow aloft remains in place over Colorado
for Friday, as the upper high sits just slightly west of the Four
Corners region. Shortwave energy embedded in the larger scale flow
coupled with monsoonal moisture working its way around the high will
work together to spark another round of scattered to numerous
showers and thunderstorms over our area, especially over the high
country. High res models are starting to hint at modest amounts of
instability Friday afternoon out on our eastern plains, somewhere in
the 800 to 1200 J/Kg range, though forecast shear amounts still seem
very uncertain. For the most part, it seems that the most favorable
shear for stronger storms will be the near the mountains, and the
highest instability will be further east out on our plains. Overall,
forecast soundings for Friday show higher DCAPE values than SBCAPE
in many locations, leading to higher chances for gusty outflows on
our plains. The SPC has added portions of Crowley, Otero, Bent,
Prowers, and Kiowa counties to a marginal risk for severe weather
for Friday, with the main risks being damaging winds gusting to 60
mph, hail, and excessive rainfall. The WPC has also outlined our
entire forecast are for excessive rainfall. Flash flooding will be
possible for area burn scars, the Chalk Cliffs, and any areas that
see heavy rains for multiple days in a row on Friday, especially in
the high country. Temperatures on Friday will be around 1 to 2
degrees below normal for most locations, with highs in the upper 80s
to mid 90s for the plains, mid 80s for mountain valleys, and 60s and
70s for higher terrain locations.

Saturday Onwards..

Models continue to bring a cold front through the forecast area
sometime late Friday or early Saturday, which will cool us down
further, and help to keep our daily chances for showers and
thunderstorms alive. Over the weekend, the upper high is forecast to
elongate and push off further to our west. This will lead to even
more cool, due northerly flow aloft for our region. Enough recycled
monsoonal moisture and shortwave energy looks to come through nearly
every day to keep daily chances for showers and thunderstorms going,
with main risks being excessive rainfall, especially over the high
country. Our temperatures look to stay 5 to 10 degrees below normal
from this weekend through at least Tuesday. The coolest days of the
period looks to be Sunday and Monday, when highs could top out in
the 70s across portions of our plains!


Issued at 413 AM MDT Thu Jul 18 2024

Dry conditions are in place early this morning, however, low level
stratus has developed across COS and PUB with COS currently
observing the lower ceilings. MVFR ceilings have been in place for
much of the overnight hours for both COS and PUB, however, continued
lowering has occurred here recently with COS falling to IFR. Think
these IFR ceilings will hold for COS, with MVFR ceilings remaining
for PUB. Don`t think these lower ceilings will be in place for too
long this morning, as flow aloft becomes more westerly. Will then
see a clearing trend through the remainder of the morning hours.
During this time, VFR conditions and dry weather will be observed at
ALS. Another day of shower and thunderstorm development is expected
across all of the terminals. Highest chances for these storms will
be during the mid to late afternoon time frame into the early
evening. Given higher confidence, did increase precip/TS wording at
all sites. While I didn`t add any mention of gusty outflow winds, do
think these are a definite possibility and will let later forecasts
address as confidence grows.