Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 241042

Area Forecast Discussion
National Weather Service Denver/Boulder CO
442 AM MDT Tue May 24 2022

.SHORT TERM...(Today and tonight)
Issued at 442 AM MDT Tue May 24 2022

Upper trough will move across Colorado today with the best QG lift
moving from south central/southeast Colorado towards the
northeast. The current low/mid level flow is ideal for snow in
South Park and the surrounding mountains, and they have done well
overnight with a couple of SNOTEL sites picking up 0.6-0.7 inch of
water equivalent. There`s a little slopover plus some weak
synoptic lift generating enough snow to make I-70 slushy at times
in Summit county, probably western Clear Creek as well.
Mild air and ground temperatures will limit the travel impact, but
it`s enough to merit a Winter Weather Advisory. While the best
upslope and synoptic scale lift will be this morning, there should
be a good crop of diurnal showers this afternoon for additional
accumulation and some areas/periods of heavy snowfall.

Elsewhere, things are going about as expected. We weren`t sure if
there would be enough cloud cover to forestall fog development,
but there are some areas of very low clouds and/or fog forming at
this hour. The warm advection aloft is generating some light rain
that will stay generally southeast of Limon and Akron during the
day, while further north there`s the surface that just got cold
enough for the fog, then a dry layer and a developing inversion
above that. So the bottom line today is a trend towards diurnal
mountain showers once the current forcing slides east, light rain
over the southeast edge of our area, and relatively stable and
drier air in between, capped by a mid level cloud deck. There`s
still a chance of showers in this in between area, but the best
bet would be early evening as the afternoon showers move off the
hills into a somewhat unfavorable environment. Perhaps the
continued east winds with some shallow moisture will still be
enough to allow the showers to live for a while. There should be
decent clearing along the Front Range by late evening. Some fog
potential, but we`ll be trending towards weak drainage winds that
will likely bring enough mixing to keep most places dry and above

.LONG TERM...(Wednesday through Monday)
Issued at 442 AM MDT Tue May 24 2022

Not many changes in the long-term forecast as trough axis exits our
region Wednesday. Surface winds will shift to the northwest
Wednesday afternoon producing breezy wind gusts up to 30 mph. Expect
dry conditions and clear skies through Thursday night.

We`ll continue to gradually warm up this week. Inverted V soundings
for the most of the region on Friday should bring dry conditions and
allow for the warmest day this week with minimal cloud cover.
Will Denver reach 90? Given the warm southwest flow and clouds
mainly forming by early evening, it is possible thus this update
includes an increase to afternoon temperatures across the region
Friday afternoon. Parts of the urban corridor and plains could
reach the upper 80s to lower 90s. The mountains and valleys join
in on the warm up reaching the lower 60s to lower 70s.

A shortwave will arrive on Saturday afternoon but the
GFS/ECMWF/Canadian differ amounts of QPF and timing. Given the small
amounts of total QPF reach 0.10-0.20 mainly focused near the
Wyoming/Colorado border in the valleys and dry air aloft being under
the ridge pattern, will keep PoPs 20-40 for a chance of scattered
showers. This shortwave extends into Sunday giving better chances of
incoming moisture for the urban corridor and plains. It seems
MLCAPE Sunday afternoon is near 100 J/kg or almost non-existent
in our CWA. These showers will most likely produce wind and small
hail versus a lightning threat.

Strong positive vorticity at 500mb from the GFS shows cyclonic
rotation in the northeastern corner of our CWA starting Monday night
into Tuesday morning. This will lead to a wetter pattern changed
across the region.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 442 AM MDT Tue May 24 2022

There will be areas of low clouds and fog around Denver this
morning. MVFR ceilings will prevail through 18z, with localized
IFR conditions until about 15z. This afternoon ceilings will be
higher, though ILS approaches to KDEN may still be needed.
Scattered showers are expected in the 22z-04z period, with
localized MVFR conditions again.


Issued at 350 AM MDT Tue May 24 2022

There is a slight chance of a thunderstorm that could produce
minor flooding over the lower elevations of the Cameron Peak burn
area in the late afternoon hours. A snow level of 8-9 thousand
feet and more stable air on the plains will preclude a threat in
the other burn areas.

The next chance of precipitation in the long-term forecast arrives
Monday which could impact the burn areas.


Winter Weather Advisory until 6 PM MDT this evening for COZ034-



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