853
FXUS65 KPUB 181716
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1116 AM MDT Sun May 18 2025

.KEY MESSAGES...

- Critical meteorological fire weather conditions across much of
  the area today with very dry conditions coupled with 30 to 50
  mph wind gusts. Areas of blowing dust possible across the San
  Luis Valley.

- Snow spreads along the Continental Divide today with 4 to 8 inches
  of new snow expected across the higher peaks.

- Cooler with scattered showers and thunderstorms on Monday.

- Patchy frost Tuesday morning along/near the Palmer Divide,
  then a slow warming trend with generally dry weather expected
  through the end of the week.

&&

.UPDATE...
Issued at 946 AM MDT Sun May 18 2025

Ran a quick update based on the latest 12z high-res model
guidance this morning. This mainly pertains to our far northeast
plains zones, eastern Kiowa County. The main concern is the
potential for convective initiation as dry air pushes moisture
to the northeast. A majority of the high-res guidance has slowed
down the push of dry air northeast, keeping dewpoints in the
lower 50s into the afternoon hours. This in turn increases
instability, with guidance suggesting 2000+ j/kg SBCAPE before
the moisture lifts northeast. The main question is...can
convection initiate before the moisture advects away from the
area. Added low pops to address this concern, as several high-
res solutions do develop convection over eastern Kiowa County
and quickly lift it northeast. However, several other high-res
solutions initiate convection just to the north of Kiowa County.
If a storm or two does develop in this area, it will most likely
become severe with large hail, wind gusts in excess of 60 mph
and a small tornado threat. The main window for severe storms is
from 2 PM through 4 PM.  Mozley

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 306 AM MDT Sun May 18 2025

Currently...Upper trough is crossing the Intermountain West, with a
closed low on the southern end of the trough moving across NV and
into UT. Strong southwest flow aloft was evident across the Four
Corners and into CO, as per satellite imagery and high elevation
obs. Temps as of 1 AM have slowly dropped into the 40s for the high
valleys, and 40s and 50s for the plains, but temps should cool
another 5-10 degrees by sunrise.

Today...The upper low as well as the low trough rotates to the east-
northeast across the Four Corners and into central CO through the
day today, with the upper jet with a 100 kt core clipping the
southern border. The brunt of the upper jet will lay across NM, so
no high wind highlights are expected. However, it will still be
windy with forecast gusts of 30 mph up to 50 mph. Models also
indicate that with the strong southwest winds, llvl moisture will be
scoured out to the northeast by midday which should eliminate any
pcpn chances for the eastern plains. Models are holding steady for
snow chances though, with 4 to 8 inches of new snow all along the
Continental Divide with some locally heavier amounts possible.
Ongoing Winter Weather Advisory in place due to the expected
snowfall and strong winds looks good and no changes are needed. The
focus of a majority of the pcpn will be the Continental Divide and
the central mts through tonight, but the eastern mts, Pikes Peak
region and Palmer Divide may see some isolated to low-end scattered
convection through the afternoon. Finally, critical fire weather
conditions will be fairly widespread across the eastern plains this
afternoon. In fact, the stronger winds and blowing dust will begin
first across the San Luis Valley, though forecast RH levels there
just do not get low enough to meet criteria. It does for the plains
though, so even though fuels are still in green-up, outdoor
activities that could start a fire are discouraged today. Plan on
high temps today in the 60s for the high valleys, and 70s to mid 80s
for the plains.

Tonight...The upper low continues to rotate to the northeast up into
WY and NE tonight, as a second upper low pinwheels south into the
Great Basin. Ongoing showers are forecast to diminish in coverage
and retreat somewhat to just the central mts. Snowfall will taper
off dramatically by sunrise Mon, and the ongoing Advisory is
scheduled to end by 6 AM. Look for overnight low temps in the upper
20s to lower 30s for the high valleys, and 40s for the plains. Moore

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 306 AM MDT Sun May 18 2025

Secondary piece of the upper trough moves through Colorado on
Monday, while surface cold front drops southward through the
plains. As a result, there should be enough upward vertical
motion and instability Monday for scattered to numerous showers
and thunderstorms at most locations, though with moisture
lacking and little in the way of upslope flow, precip amounts
for the most part will be light (under a quarter inch). Showers
fade away Mon night as trough departs, with clearing skies by
Tuesday morning. Still appears there will be a risk of some
patchy frost on the plains shortly after sunrise Tue, mainly
across nrn El Paso County, where mins could fall into the mid
30s.

Seasonably mild and dry on Tuesday, then warmer Wed as upper
ridge builds over the Rockies. Modest low level moisture return
develops on the plains Thu as s/w trough passes through the nrn
Rockies, and at least a few model solutions hint at isolated
t-storms possible on the plains Thu afternoon/evening. Confidence
is still low on any precip at this point, and won`t introduce
any pops back into the forecast for now. W-SW flow aloft then
begins to strengthen Fri into the weekend, potentially shunting
any moisture eastward while boosting max temps up to well above
average levels.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1113 AM MDT Sun May 18 2025

KALS...overall VFR conditions through the next 24 hours. Strong
southwest winds gusting in excess of 40 kts through this
afternoon could produce areas of BLDU and reduced VIS. Winds
will decrease this evening into Monday morning with CIGS
lowering to near 5 kft late in the period.

KCOS and KPUB...gusty south to southwest winds will impact both
terminals through this afternoon with gusts 35 to 40 kts
possible. A frontal boundary will push south across the region
late tonight into Monday morning shifting winds north to
northeast, along with increasing chances for precipitation,
lowered CIGS and reduced VIS.  Mozley

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 6 AM MDT Monday for COZ058-060-
066-068.

&&

$$

UPDATE...
SHORT TERM...MOORE
LONG TERM...PETERSEN
AVIATION...MOZLEY