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Area forecast discussion
National Weather Service Pueblo Colorado
1108 PM MDT Sat Aug 24 2019

Short term...(this evening through sunday)
issued at 250 PM MDT Sat Aug 24 2019

Initial meteorological focus is on the potential for strong
to severe thunderstorms over the far southeastern Colorado
plains from later this afternoon into this evening, with
recent analysis indicating cape values 2000 to 3000+ j/kg,
Li's of -4c to -6c and bulk shear values nearing 30 knots at times
over far southeastern Colorado locations.

In addition, latest GOES satellite imagery indicating developing
cu fields from Prowers County into western Baca and Las Animas
counties, therefore Storm Prediction Center marginal to slight risk of severe
thunderstorms over portions of Kiowa, Prowers and Baca counties
from later this afternoon into this evening remains feasible and
weather forecast office Pueblo will monitor closely and issue warnings as warranted.

Elsewhere over southern Colorado, increased primarily high clouds
noted over the majority of the County Warning Area today in combination with
generally above seasonal later August afternoon temperatures and
localized wind gusts around 40 mph at times, near locations such
as Leadville and Cottonwood Pass, allowing localized elevated fire
conditions to be noted

For this evening, will maintain isolated pops favoring Kiowa,
Prowers and Baca counties, including the potential for some
severe thunderstorms.

Then from later tonight into Sunday, expect dry conditions in
combination with above seasonal temperatures as upper ridging
builds into southern Colorado. Localized/elevated fire weather
conditions will also be noted at times, primarily during Sunday
afternoon.

Long term...(sunday night through saturday)
issued at 250 PM MDT Sat Aug 24 2019

Sunday night:

Dry conditions will continue for Sunday night and Monday morning
in response to the consistent northwesterly flow aloft. Precipitable water
values will be around will be around 0.3" over the mountains and
mountain valleys, so chilly overnight temperatures are expected.
The San Luis valley will likely be lower than guidance suggests
with low temperatures in the the low 40s, Creede will likely be in
the low 30s, Westcliffe in the upper 30s, the plains in the low
to mid 60s, the upper Arkansas River valley in the mid to upper
50s, and the mountains in the 30s to 40s.

Monday:

A cold front is still on track to move across southern Colorado
Monday morning. At this point in time the cold front should reach
El Paso County during the mid morning hours and reach the New
Mexico border by mid afternoon. The propagation speed seems to be
slowing down with model trends, so it is possible that the front
stalls over south-central Colorado. The European model (ecmwf) still indicates that
weak showers and thunderstorms will develop over the eastern
mountains as the front reaches them, whereas the GFS and the NAM
continue to have a dry passage. Since the precipitable water values are so low
over the mountains, I anticipate the GFS and the nam's solution to
be the correct solution.

The cold front is expected to cool the temperatures by around 10f
compared to Sunday afternoon, but that will be dependent on how
fast the front moves across Colorado and if the front doesn't
stall over south-central Colorado. For example, if the front
stalls north of La Junta, the high temperature will still be in
the upper 90s instead of the lower 90s. That outcome is just a
thought exercise, since I believe the front will make it across
Colorado.

Tuesday:

The Post frontal atmosphere will remain cooler and the winds will be
from the east-southeast, which is an orientation efficient for flow
up the mountains. Previous models runs have hinted at widespread
precipitation over the southern Sangre de Cristo Mountains on
Tuesday afternoon, which would pose a flash flooding risk over the
Spring burn scar, but that outcome hasn't been consistent. The
more likely outcome will be an isolated thunderstorm over the
southern sangres and Raton Mesa.

Wednesday:

The upper-level ridge begins to develop over the Desert Southwest,
which will allow (eventually) for a Pacific based moisture tap to
advect over western Colorado. As for Wednesday some isolated
thunderstorms are possible over the higher elevations, in
particular the Sangre de Cristo Mountains. The La Junta cyclone
will develop in the afternoon hours, which will tighten up the
moisture gradient over the eastern plains, and with the
northwesterly flow aloft ejecting shortwave disturbances embedded
in the upper level flow, some thunderstorms are possible.
Northwesterly flow aloft accompanied with low level southerly flow
will allow for plenty of wind shear, and the cape values near the
Kansas border is forecast to be around 1500 - 2000 j/kg,
therefore the potential for severe weather thunderstorms are
possible. The rest of the region is forecast to be generally dry.

Thursday through sunday:

Pacific based moisture will continue to propagate towards Colorado.
More numerous thunderstorms are anticipated over the mountains on
Thursday afternoon, but there are large discrepancies between the
GFS and the European model (ecmwf). The European model (ecmwf) has generally dry outcome until
Saturday afternoon when a front develops over the region, but the
GFS has more frequent daytime mountain thunderstorms Thursday and
Friday, with the front developing over the region on Friday, instead
of Saturday. So the timing on with the frontal passage is uncertain,
but what appears to be certain is that when the front passes there
will be widespread precipitation over the mountains and the plains.
On Sunday, the models are in agreement that the ridge will
propagate north over Colorado, resulting in dry conditions.

&&

Aviation...(for the 06z tafs through 06z Sunday night)
issued at 1107 PM MDT Sat Aug 24 2019

VFR conditions through the next 24 hours at all three terminals.
West to northwest winds will increase for the afternoon hours with
gusts of 20 to 25 kts for all terminals. Winds will subside Sunday
evening. Mozley

&&

Pub watches/warnings/advisories...
none.

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