749
FXUS65 KPUB 181747
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1147 AM MDT Tue Jun 18 2024

.KEY MESSAGES...

- Non zero threat of a couple of landspouts over the Baca County region
  late this afternoon/early evening.

- Red Flag conditions over the San Luis Valley today; near
  critical conditions along the immediate CO/NM border this
  afternoon.

- Strong cold front will push south down the plains this AM and stall
  along the CO/NM border.

- Showers and storms over the far eastern plains tonight.

- Around 15F colder than average for this time of year over the plains
  on Wednesday.

- Anomalously high precipitable water (PWAT) values are
  expected over the mountains Thursday and Friday - will lead to
  heavy rains and the potential for flash flooding.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 317 AM MDT Tue Jun 18 2024

Currently...

An interesting next 24 hours is in store for the fcst area.

On the regional scale, a rather impressive cold front is pushing
southeast across Colorado early this morning. At 2 AM, this front
extended from roughly KAKO-KDIA and then west-southwest across the
mtns from Eagle CO to Grand Junction. Rather impressive pressure
rises were noted behind this front (>10mb/3hr). over the plains, a
sharp dryline was noted from the KAKO area south to KLHX to Kim and
southward along the NM/TX border. East of the dryline 60+ dwpts were
noted while behind the dryline, TDs were in the 20s. A strong low
level jet was howling over far eastern CO as winds were gusting to
55 to 65 mph in Lamar.

Today...

The front over NE CO will continue to push south and should blast
across the Palmer Divide around 10 UTC and continue to push south,
reaching the US50 corridor during the 12-13 UTC time frame then down
to the NM border by late morning. At this time the front is fcst to
stall along the CO side of the Raton Mesa. As the front goes by,
northerly winds will usher moister and cooler air into the area, and
winds will shift to an upslope component a few hours after frontal
passage.

As for sensible weather, it will be a rather nice day over the
region, Temps will be noticeably cooler over most of the region wit
max temps in the 80s over El Paso county and low 90 over the lower
Ark River Valley. Mid 90s is expected over the Raton Mesa.

The interesting weather today will be along the stalled front late
this afternoon into the early evening hours. This front is expected
to stall and convection will likely erupt along the boundary late
this afternoon. At this time, exactly WHERE the convection initiates
still is a bit uncertain, but given the stalled boundary, well mixed
EML and moisture advecting in behind the front, conditions will be
favorable for landspout tornadoes to develop.

With upslope pushing into the mtns late this afternoon, showers and
thunderstorms will be possible over the higher elevations of the
Pikes Peak region.

Tonight...

For early this evening, isolated showers and storms will be possible
along the east slopes of the mtns/plains interface.

Over the far eastern plains early this evening, showers and storms
will be ongoing, especially along the KS/CO border eastward.
Some of the storms could be strong and produce locally heavy rain.

As the evening progresses, showers and storms will build westward
over the plains, pushing back to the KLHX area by the early AM hours
and possibly back to the I-25 corridor towards sunrise. The overall
best chance of showers and storms later tonight will be generally
east of a line from KLHX to Kim. Tomorrow morning it should be
overcast over all of the southeast plains. IT should remain dry over
the mtns. /Hodanish

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 317 AM MDT Tue Jun 18 2024

Wednesday:

A cold front will have passed on Tuesday which will leave a post
frontal airmass over southern Colorado for Wednesday. The
result will be high temperatures roughly 15F lower than the
normal for this time of year for the eastern plains with values
in the 60s and 70s. The mountain valleys will not get the full
effects of the passing cold front, but the upper Arkansas River
Valley will be in the low 70s and the San Luis Valley will be in
the upper 70s to low 80s. The surface flow will be from the
northeast across the plains, which is an upslope flow regime for
the eastern mountains and south of Highway 50 - this will aid
in stratiform rain over the plains. In my AFD from last night I
stated that there may be some instability leading to embedded
thunderstorms unless the temperatures continued to trend
downward - at this point I am confident enough to say that
convection should stay away from the plains on Wednesday,
however, some rumbles of thunder are expected over the
mountains.

Thursday:

The cool temperatures do not last long - Thursday returns to the 90s
over the plains and the upper 70s to 80s over the mountains valleys.
Instability also returns, as well, with roughly 1000 J/kg of CAPE
over the mountains and over northern El Paso County. Currently the
main lifting mechanism will be a weak shortwave passing over the
region, but convection initiation will be focused over the
topography. There may be some heavy raining thunderstorms over the
mountains, so the Decker and the Spring burn scars will have to be
monitored. All of this is associated with a big surge of Gulf of
Mexico moisture - this moisture will last through the weekend. PWAT
values are around 100-150% over the plains throughout the day on
Thursday, but the mountains and mountain valleys reach around
200% of normal.

Friday through Monday

The PWAT values mentioned in Thursday`s period increases over
the mountain and mountain valleys with up to 300% of normal
during the morning and the afternoon on Friday. There is a wave
passing overhead, so the anomalously high PWAT values and
reasonable lift overhead may create some heavy raining
thunderstorms over the mountains - flash flooding will need to
be monitored over the mountains on Friday. The lift, at this
point in time, is confined over the mountain and mountain
valleys, leaving the plains dry.

Weak riding aloft will inhibit widespread convection from Saturday
through Monday, but isolated thunderstorms will be possible across
the region as a weak wave embedded in the upper level ridge passes
overhead. Perhaps an isolated severe thunderstorm is possible,
particularly on Sunday.

The 100s return to the plains early next week, whereas the mountain
valleys will reach the upper 80s to low 90s.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1146 AM MDT Tue Jun 18 2024

KALS: VFR conditions are expected through 24 hours, with gusty
southwest winds to around 25 knots this afternoon. Mid level clouds
will increase overnight towards the end of this forecast period.


KCOS and KPUB: Gusty winds this afternoon will shift between
easterly and southeasterly throughout the afternoon, with mid-level
clouds slowly increasing. Overnight tonight, winds will turn more
easterly and the upslope will bring in more cloud cover, with low
stratus blanketing the area by morning. Along with this, widespread
rain showers are expected, starting between 10-12Z and lasting for
several hours. Once the rain departs, the clouds are expected to
remain through the end of the period. While rain is not currently
expected to lower visibility much, cloud ceilings will waver between
low MVFR and IFR conditions.


&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 7 PM MDT this evening for COZ224.

&&

$$

SHORT TERM...HODANISH
LONG TERM...SKELLY
AVIATION...GARBEROGLIO