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143
FXUS65 KPUB 061526
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
926 AM MDT Mon May 6 2024

.KEY MESSAGES...

- Critical fire weather conditions are expected over parts of
  the region today, Tuesday, and again on Wednesday.

- Strong winds in the mountains will spread east over the
  southeastern Plains early this morning.

- Wind driven snow will end in the mountains later this morning.

- Strong winds will pick up again on Tuesday with blowing dust
  possible across the southeastern Plains, I-25 corridor, and
  valleys with blowing snow possible for the higher terrain.

- A disturbed pattern will be in place late this week into the
  weekend with scattered showers and thunderstorms possible
  along with high elevation snow.

&&

.UPDATE...
-- Changed Discussion --
Issued at 921 AM MDT Mon May 6 2024

Issued a High Wind Warning for Pueblo County until 3 PM, due to
winds exceeding the threshold currently over portions of the
county, as well as model guidance suggesting that gap flow
could keep winds sustained above the threshold as winds turn
more west-northwesterly this afternoon. -Stewey
-- End Changed Discussion --

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 415 AM MDT Mon May 6 2024

Currently...

10 mb 3 hr pressure rise was noted over the 4 corners while 4 mb
pressure falls note over the plains. Front was likely somewhere in
the San Luis Valley/Sangres at 3 AM and was pushing east. Winds have
been quite squirrelly over the plains this morning with winds
becoming quite gusty at times along the I-25 corridor and then
decreasing wot light and variable. Farther east a strong steady
southerly winds was noted. Lots of showers were noted over the
higher terrain while dry conditions noted over the plains. A
very sharp dryline was slowly progressing west over the eastern
plains, with 50 dwpts over the far eastern counties and 20s and
30s west of the dryline.

Today...

Main concerns today will be strong winds (especially this morning)
and fire weather conditions today. Strongest winds will appear to
occur this AM, with the strongest winds along the plains/mtns
interface, especially on the east slopes. These winds will gradually
push out onto the plains as we get closer to sunrise this AM, and
expect we will reach critical fire weather conditions where fuels
are receptive by mid morning. Overall, it is going to be a windy day
over the entire region, with winds slowly decreasing this afternoon.

As of now, there are no high wind hilites for lower elevations of
Pueblo and El Paso county, but I cannot rule out one or two high
wind events occurring for a short duration as the front moves through
over these areas.

Although strong shear and instability is occurring out east early
this AM, atmosphere will be too stable for convection to develop.

Snow in the mtns along the divide should decrease as the morning
progresses.

Tonight...

Winds will decrease significantly over the plains after sunset and
will decrease over the mtns, but will still be gusty at times,
especially at higher elevations. Any precip during the nighttime
hours will be predominantly over the central mtns, especially north
of Cottonwood Pass.

Humidity recovery will be poor tonight over the plains, especially
south of US50.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 415 AM MDT Mon May 6 2024

There is GFS/NAM/ECMWF agreement that the strong closed upper low
will be centered near the MT/SD/ND tri-state border on Tuesday.
This will put SE Colorado in a strong westerly mid-level flow
well south of the feature. With 50kts winds at 700mb on Tuesday
afternoon, would not be surprised to see some of this translate
down to the surface. The San Luis Valley comes close to criteria
for a High Wind Watch, with sustained winds of 30-40 mph and
gusts to 40-50 mph, but have decided to hold off on this for
now as it is marginal. Future forecast packages may need to
issue High Wind products as confidence increases.

700mb flow and moisture also suggest that some upsloping snow
showers will be possible for the Sawatch Range on Tuesday, with snow
finally waning Tuesday night. Any accumulation will be light,
generally less than an inch. Strong winds on Tuesday will make
blowing snow possible for the higher terrain of the Sawatch Range
and San Juans Mountains. Meanwhile, blowing dust will be possible
for the San Luis Valley, I-25 corridor, and SE Plains. Given the
strong winds on Tuesday coupled with RH values dropping into the
teens in the San Luis Valley and portions of the SE Plains that are
very dry, the Fire Weather Watch was upgraded to a Red Flag Warning.

The upper low will weaken as it slides southeastward across South
Dakota into Wednesday. This will allow for winds to decrease and for
the forecast to dry out across the area Tuesday night into
Wednesday.  Winds should again on Wednesday be strong enough for
fire weather conditions in similar areas, and thus a Fire
Weather Watch was issued for the same areas except for Baca
County where the winds may be just shy of hitting criteria for
fire weather conditions.

More uncertainty begins to enter the forecast Thursday into the
weekend. There are GFS/ECMWF/Canadian ensemble differences in
resolving an elongated mid-level trough extending from the northern
Plains southwestward into the Rockies. The operational models are
leaning toward an upper low closing off over Utah Thursday into
Friday with a short wave passing northeast of the area. Regardless
of how the trough evolves, it should lead to an unsettled pattern
for the area late this week with the chance (30-40% probability) for
showers and thunderstorms for the lower elevations and snow showers
for the highest terrain Thursday into Friday. For the weekend, the
forecast remains aligned with the National Blend of Models (NBM)
with the chance of showers and thunderstorms for the lower
elevations and snow showers above 9500 ft.

For temperatures, highs will be near normal values on Tuesday,
cooling to 5-10 degrees below normal Wednesday into Friday and then
back closer to normal values for the weekend. /04-Woodrum/

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 452 AM
MDT Mon May 6 2024

Main concern today will be strong gusty west winds at all 3 taf
sites, KPUB, KALS and KCOS. Gusts to 45 to 55 mph will be
possible, mainly this morning with winds gradually decreasing
late this morning into the afternoon time period. Winds should
significantly decrease after sunset. VFR anticipated next 24
hours at all 3 taf sites.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
Winter Weather Advisory until 10 AM MDT this morning for
COZ058-060.
Red Flag Warning until 10 PM MDT this evening for COZ224-225-
232-233-237.
Red Flag Warning from 9 AM to 10 PM MDT Tuesday for COZ224-225-
232-233-237.
Fire Weather Watch from Wednesday morning through Wednesday
evening for COZ224-225-232-233.
High Wind Warning until noon MDT today for COZ072>075-078>085-
087-088.
High Wind Warning until 3 PM MDT this afternoon for COZ086.
-- End Changed Discussion --

&&

$$

UPDATE...STEWARD
SHORT TERM...HODANISH
LONG TERM...WOODRUM
AVIATION...HODANISH