543
FXUS65 KPUB 012334
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
534 PM MDT Wed May 1 2024

.KEY MESSAGES...

- Critical fire weather conditions linger into this evening over the
  San Luis Valley, then return to the Valley again on Thursday.

- Isolated thunderstorms possible this evening over the central
  mountains/Palmer Divide/Kiowa County.

- Generally unsettled weather late this week into the weekend. A
cold front will arrive late Friday and bring scattered showers and
storms to the area.

- Temperatures warm up late this weekend into early next week.
  Critical fire weather conditions will continue to be a
  concern.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 254 PM MDT Wed May 1 2024

Detailed discussion:

Currently, dry air/gusty west winds a little slow to push east away
from the mountains this afternoon, with observations at 2 pm
suggesting stronger winds remain confined to areas generally west of
the I-25 corridor. As a result, low level moisture was holding on
slightly longer than forecast over the far sern plains, and some
modest CAPE of 400-800 J/KG has developed along the KS border,
though deeper instability (CAPE of 2000+ J/KG) and tighter moisture
gradient was farther located farther east in KS. Plenty of wind and
dry air over the mountains, with southwest winds gusting 30-50 mph
over most peaks and valleys.

Tonight...Despite low level moisture lingering over the plains, most
CAMs (including the experimental WoFS) keep convective initiation
well east of the CO/KS border late this afternoon/evening, closer to
the dryline and deeper instability. Suppose we could pop a storm
over ern Kiowa County later this evening along the srn edge of the
better upper level forcing, though bulk of the activity should stay
farther east. Out west, scattered showers/isolated thunderstorms
will remain possible into the evening over the mountains, and some
weak convection may form along the Palmer Divide, as cold front
pushes south this evening and slightly better moisture comes in
behind the boundary. Red Flag Warning was verifying well in the San
Luis Valley and will keep it up into the evening. Will also keep the
plains warning up as well, as many models insist gusty wly winds
will develop, and a few obs have started to stir (Raton and
Walsenburg) as of 230 pm. Most precip ends after midnight, with
gusty north winds on the plains gradually weakening toward Thursday
morning.

Wednesday...Still breezy to windy in the San Luis Valley as brisk
wly flow aloft persists across the area, and will upgrade the Fire
Weather Watch to a Red Flag Warning for the afternoon. Generally
dry/slightly cooler conditions expected over the area in the wake
of the cold front, with just enough moisture/instability lingering
for perhaps some weak convection over the southeast mountains and
Palmer Divide in the afternoon. Max temps will end up around 3-7
degf cooler than Wed numbers.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Issued at 254 PM MDT Wed May 1 2024

The upper level trough will continue to push through our area on
Friday, continuing our trend of gusty surface winds and critical
fire weather conditions across parts of our area. As of now, main
fire weather concerns will once again be across the San Luis Valley,
where the more humid air from behind the front will not reach.
Additionally, with gusty west-southwest surface flow we may also see
some spotty critical conditions over parts of the southern I-25
corridor due to gap flow. However, some of these areas remain pretty
green as far as fuels go, so that may negate the need for any
highlights beyond the valley. High temperatures will increase a bit
from Thursday, with high-60s over the valleys and higher terrain
while the eastern plains climb into the mid-high 70s.

Late Friday afternoon into Friday Night, a secondary wave will pass
through the area aloft, sending a cold front south across the
plains. Just ahead of it, showers and thunderstorms will be possible
thanks to low-level convergence, mainly close to the border. At this
time, most of the activity in the models is east of the CO-KS
border, but a few high-based storms over our far eastern counties
will be possible. A few scattered storms may also be possible along
the Palmer Divide thanks to localized upsloping.

Moving into this weekend, a strong upper low will move down from the
Pacific Northwest and onto the coast. Saturday will remain slightly
cooler and somewhat unsettled thanks to lingering post-frontal
moisture, with a few isolated to scattered showers across the higher
terrain. Additionally, we may also see some lingering showers and
storms over our far southeastern zones, leftover from activity once
the front has fully moved south of our area.

Sunday will warm quickly, with 70s to low-80s across the area. The
main change to the long-term forecast in the last 24 hours has been
much faster movement of the upper low as it transitions into our
region. As the low digs down into the Four Corners Region Sunday
evening, scattered showers and storms will pick up across the
Central Mountains. By Monday, as the low continues to trek east
along with the main axis of the upper trough, precipitation will
largely depend on the track of the low. With the models speeding up
progression somewhat, along with a more northbound track in recent
runs, precipitation may be somewhat confined to the higher terrain
and the Pikes Peak Region, with the trough moving off to our
northeast by Monday night. This is largely what the current NBM
guidance suggests. This may also hint at a more windy start to the
work week, which would mean a heightened chance of more widespread
critical fire weather conditions along with warming
temperatures.

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 534 PM MDT Wed May 1 2024

VFR conditions are expected at all three TAF sites, KCOS, KPUB, and
KALS, for the next 24 hours. A cold front has pushed through KCOS
this hour, and is expected to arrive at KPUB within the next hour as
well. Gusts to around 30kt will be possible at both stations until
around 08Z tonight behind this front. North winds are expected at
KALS by around 05Z as well, though they will be much lighter. Winds
weaken and become more northeasterly through the early morning
hours at both KCOS and KPUB, before eventually swinging around to
southerly and southeasterly at both stations tomorrow after 18Z.
West-southwesterly gusts to 30kt are expected at KALS tomorrow.
Precipitation is not expected at any station through this TAF
period.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT this evening for COZ224-232-
233-237.
Red Flag Warning from noon to 9 PM MDT Thursday for COZ224.
Fire Weather Watch from Friday afternoon through Friday
evening for COZ224.

&&

$$

SHORT TERM...PETERSEN
LONG TERM...GARBEROGLIO
AVIATION...EHR