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fxus65 kpub 212058 

Area forecast discussion
National Weather Service Pueblo Colorado
258 PM MDT Sat Sep 21 2019

Short term...(this evening through sunday)
issued at 255 PM MDT Sat Sep 21 2019

Critical fire weather conditions continue until around 8pm over the
San Luis valley this evening and near critical fire weather
conditions will remain over the upper Arkansas River valley, the
mountains, and southern I-25 corridor until around sunset.
Conditions are expected to remain dry throughout the evening hours
for the region. By around 2200 MDT this evening a cold front will
make its way into northern El Paso County and will spread south-
southeasterly, arriving to the New Mexico border by around 0300 to
0400 MDT tomorrow morning. Behind the cold front over El Paso
County there is the possibility for scattered showers during the
overnight hours. According to thermodynamic soundings the lowest
100 mb is still fairly dry, making it difficult for rain to make
it to the ground. What there is high certainty of is a low cloud
deck forming behind front, spreading across the plains.

As the trough axis aloft propagates across Colorado, dry air will be
associated with it. The dry air will plummet temperatures overnight
over the mountains and mountain valleys. Places like Creede will be
in the mid 20s, the San Luis valley will be in the upper 20s, and
Leadville is expected to be in the mid 20s. The cold temperatures
will prompt a freeze warning over the San Luis valley from 0400-0800
MDT on Sunday morning. Crops are at risk for impact. Outside of the
reaches of the valley floor, near the mountains, temperatures will
still be near freezing and likely won't see a hard freeze, but there
is confidence over the valley floor. Over the plains the low
temperatures will be in the mid 40s to low 50s and the teens to 20s
over the mountains.

Tomorrow afternoon will be much cooler and will actually be average
for this time of year over the region. Expect high temperatures over
the plains to be in the upper 70s, the mountain valleys in the low
70s, and the mountains to be in the 40s to 50s. Over the southern
reaches of the San Luis valley will be near critical fire weather
conditions, but fire weather conditions will not be met.

Long term...(sunday night through saturday)
issued at 255 PM MDT Sat Sep 21 2019

Beautiful Fall weather is expected for much of the week ahead with
temperatures remaining above normal east of the mountains and around
normal for the higher elevations. The southern mountains will have
the best chance for precipitation while dry weather continues on the

From Sunday night into Monday, a transient upper level ridge moves
across the state with dry and mild temperatures. An upper level trof
moves across the Great Basin with an upper low cutting off over
Southern California. The northern stream energy stays well to the
north of Colorado with only a weak frontal boundary moving through
the eastern plains Tuesday night into Wednesday. Could see a few
showers or thunderstorms in the San Juans during this period, but
most areas will remain dry. High temperatures Monday and Tuesday on
the plains will be in the 80s with 70s in the higher valleys, and
50s and 60s in the mountains. With the weak front moving through the
plains Tuesday night into Wednesday, high temperatures will be a few
degrees cooler on the plains Wednesday.

On Thursday, the closed upper low lifts northeastward with a strong
low pressure system moving onshore in the Pacific northwest. The
open wave moves across southeast Colorado on Friday. Precipitation
chances increase along and west of the mountains on Thursday. High
temperatures will remain warm with highs in the upper 70s to mid 80s
on the plains Thursday and Friday, upper 60s in the higher valleys
and 40s and 50s in the mountains. Could see some scattered snow
showers in the higher elevations as well.

The trof remains over the western portion of the U.S. With an
amplifying ridge over the eastern half of the country. We remain in
southwest flow aloft Friday night through Saturday. This keeps much
of south central and southeast Colorado dry and warm. Highs will top
out from 80 to 90 on the plains, lower 70s in the high valleys, and
50s and 60s in the mountains.



Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 255 PM MDT Sat Sep 21 2019

VFR conditions are anticipated for kals, kcos, and kpub throughout
the next 24 hours. Some showers will develop in the vicinity of kcos
during the overnight as a front passes by, but the most likely
outcome will be low ceilings, which will also impact kpub. At this
point in time, flight categories are expected to remain VFR.


Pub watches/warnings/advisories...
red flag warning until 8 PM MDT this evening for coz224.

Freeze warning from 4 am to 8 am MDT Sunday for coz069>071.



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