National Weather Service Forecast Discussion

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242
FXUS65 KBOU 011958
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
158 PM MDT Fri May 1 2026

.KEY MESSAGES...

- Warmer and drier conditions expected for the weekend.

- Unsettled weather returns Monday night through Wednesday with
  increasing chances for mountain snow and rain showers over the
  plains.

&&

.DISCUSSION /Through Friday/...
Issued at 126 PM MDT Fri May 1 2026

The remnants of the storm system that brought some rain and snow
to the region continues to weaken as the parent trough axis
continues to push well to the east of the forecast area. Satellite
shows mostly fair weather cumulus across the forecast area, and
any afternoon rain/snow showers across the higher elevations
should be quite weak. Temperatures across the plains have warmed
into the upper 50s to low 60s and are currently close to forecast
highs today. Clear skies overnight should allow temperatures to
fall back into the low to mid 30s once again overnight.

Weak ridging is expected to develop for the weekend, leading to a
period of above normal temperatures. Saturday will be sunny with
temperatures across the plains settling around 70F. While some
increase in cloud cover is likely for Sunday, highs should also
warm several degrees with mid-level temperatures warming a few
degC with a bit more of a downslope component as well.

As we enter next week, a return of cooler and unsettled weather
looks increasingly likely... beginning late Monday and continuing
through Wednesday. Guidance is reasonably consistent handling the
main synoptic scale features during this period, with a broad
upper low near west-central California Monday afternoon, with a
stronger upper trough centered near Manitoba/western Ontario. The
upper low is expected to drift eastward towards the desert
southwest by mid-week, while a lobe of the longwave trough pushes
down towards eastern Wyoming. Somewhere between these two
features, a quasi-stationary frontal boundary is likely to be the
focal point for an organized round of precipitation... eventually
transitioning to more of a traditional upslope flow regime here
by Tuesday or Wednesday as the front pushes further to the south.

A review of the last couple cycles of deterministic and ensemble
model data shows a variety of solutions for both temperatures and
QPF for our CWA, largely dictated by how the cutoff low is
absorbedby the northern trough, and where the initial
frontogenesis sets up. The ECMWF and its ensemble remain on the
bullish side, with 10th percentile QPF through Wednesday evening
over a half an inch... while the GEFS has several far drier
members. While these solutions are certainly a reason to have some
optimism, it`s hard to ignore how precarious the overall setup
appears... especially since we just went through a similar process
over the last several days. Our overall forecast thoughts have
not changed significantly (despite the far too bullish NBM PoP
grids for Tuesday), and we`ll continue to watch the period
closely.

Beyond that system, broad ridging is expected to redevelop across
the region, leading to a return of warmer and drier conditions to
end next week.

&&

.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 1147 AM MDT Fri May 1 2026

Weak winds are expected at DIA this afternoon, tonight and on
through Saturday. Directions should adhere to normal diurnal wind
patterns. The drainage winds should kick in around 06Z tonight at
speeds of 10 knots or less. There will be no ceiling issues.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Hiris
AVIATION...66

NWS BOU Office Area Forecast Discussion