547
FXUS65 KPUB 172326
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
526 PM MDT Fri May 17 2024

.KEY MESSAGES...

- One or two strong storms tomorrow generally north of US50

- Warm dry and windy for Sunday and Monday with thunderstorms
  possible again by Tuesday across northern portions of the
  area.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 200 PM MDT Fri May 17 2024

Currently...

A beautiful day across he region this afternoon. Sat pix showing
mostly sunny skies over the area with temps in the 80s eastern
plains and 70s most of I-25 corridor. Valleys were in the 50s with
30s and 40s mtns.

Rest of Today into Tonight...

Although an isolated shower could be possible over the higher
terrain area, expect dry weather. Gusty winds will continue over the
central mtns otherwise winds should be relatively light over the
remainder of the region, with typical nocturnal flow over the
plains.  Seasonable mins expected tonight with 50s plains and U30s
valleys.

Tomorrow...

Main concern this day may be one or two strong storms over the
Palmer Divide region by mid to late afternoon. Although shear will
be ample, low level upslope flow will only have marginal CAPE values
(500-700 J/kg) by late afternoon. Storms will likely get going by
mid afternoon over the Pikes Peak Massif region and then push east
over the modest unstable airmass over the Palmer Divide. This
will allow for one or two of the cells to become strong, with
gusty winds and small hail possible. Area is in general thunder
at this time but would not be too surprised to see this area
upgraded to marginal with later SPCs forecasts.

Although all areas could see a rumble of thunder tomorrow, the
overall best chances will be from US50 northward, especially
during the mid to late afternoon time period.

Max temps tomorrow over the plains will be similar to todays max
temps, while the valleys may be 2-3F warmer than today. /Hodanish

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Issued at 200 PM MDT Fri May 17 2024

Thunderstorms will linger into Saturday evening across northern
portions of the forecast area as convective outflows off the
Palmer Divide drive another reinforcing northerly surge
southward across the southeast plains. While shear will be
sufficient for a strong storm or two, low level moisture and
resultant CAPE may be the more limiting factor, but a strong
storm or two will be possible into the evening hours.

Increasing southwest flow Sunday and Monday will bring predominantly
dry and windy conditions to southern CO along with above normal
temperatures.  Highs will be pushing 90 for portions of the
southeast plains these days. Critical fire weather conditions will
be in place but fuels have entered green up in all but the lower
elevations of zone 225 (Sangres and Wet Mountain zones) which is
a fairly limited area. Do not anticipate the need for fire
weather highlights at this time but spotty critical fire weather
conditions will be possible.

Will need to monitor the position of a frontal boundary across
the far eastern plains on Monday as this could be the focus for
a strong to severe storm or two. NAM12 and EC back the front
into portions of Prowers and Kiowa county in the afternoon with
the potential for some pooling CAPE 1000+ J/kg and deep layer
shear over 50 kts given low level easterly flow beneath strong
southwest flow aloft. GFS and Canadian keep the front to the
north and east of the area. NBM CAPE probabilities suggests
NAM12 is in the 95th+ percentile for CAPE which could be
overdone given the strong southwest flow aloft, but will need to
monitor this as sometimes the Nam12 is better at picking up
these finer details, especially if a slower upper trough
solution continues to amplify out west.

Convective outflows from thunderstorms across northeast CO may help
drive the front southward through the SE plains Monday night.  This
will bring a cooler Tuesday across the region with an uptick in
showers and thunderstorms and higher elevation snow, especially
north of highway 50 as the upper trough moves through western
and northern CO through Tuesday evening. A few inches of snow
accumulation will be possible across the higher peaks of the
central mountains. Jury is still out on storm coverage and
strength across the plains as a more northern storm track across
CO would suggest best chances would be to the north of the
area. Subtle details on the position of the front reinforced by
convective outflows from the night before could point to
increased chances farther south, though confidence remains low
at this point.

Dry and breezy conditions return late week as we remain under west
to southwest flow aloft to the south of the primary storm track.
-KT

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 520 PM MDT Fri May 17 2024

VFR at all taf sites the next 24 hrs. Weak wave and moderate
instability will lead to scattered -shra/isolated -tsra over the
mountains Sat after 18z, and some weakening convection will
spill eastward onto the plains after 20z. Will include a vcsh
at both KCOS (after 20z) and KPUB (after 21z), but won`t
mention any vcts yet, as instability for tsra away from the
higher terrain looks marginal. Even if storms don`t occur, both
sites will likely see a period of gusty/erratic winds in the
late afternoon as weak convection/virga move through.

Won`t include any convection in the KALS forecast at this point
as most activity stays north, though some gusty outflows from
distant storms may be possible, especially after 22z.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...HODANISH
LONG TERM...KT
AVIATION...PETERSEN