National Weather Service Forecast Discussion

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749
FXUS65 KBOU 241852
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1252 PM MDT Sun May 24 2026

.KEY MESSAGES...

- Warm conditions expected through the week, with daily showers
  and a few thunderstorms expected most days in the
  afternoon/evening.

- Tuesday will bring windy conditions to the plains and potential
  for elevated fire weather conditions in areas that see little/no
  rain.

- Wednesday appears to be the most active day with more widespread
  shower and thunderstorm coverage.

- After somewhat of a lull Thursday, thunderstorm potential will
  increase again Friday into the weekend.

&&

.DISCUSSION /Through Sunday/...
Issued at 1212 PM MDT Sun May 24 2026

Scattered showers dot the high country at this hour and will
continue through the afternoon, with development of isolated
thunderstorms as well given modest instability. This activity will
struggle to hold together in its attempt to exit the foothills,
encountering an only marginally unstable environment over the
urban corridor and essentially none farther east. Thus, expect
cells to gradually decay as they progress east through the lower
elevations, with plenty of virga and some light showers being most
numerous along and west of I-25.

A developing negatively tilted trough over the Desert SW will
force a transition to prevailing southerly flow for Monday and
consequently a modest increase in warm moist advection, enough to
provide for slightly unstable conditions by the afternoon across
the plains. High-based showers and a few thunderstorms will thus
become more likely for the lower elevations, although rainfall
amounts will be light and localized, with gusty outflows being the
more common feature considering the very steep low-level lapse
rates and warm surface temperatures into the mid 80`s to lower
90`s.

The south/southeast flow pattern is reinforced on Tuesday,
allowing for greater vapor transport into the region, seeing
precipitable water values climb to around 0.90". However, this
will be countered by a more stable airmass and a general lack of
forcing, limiting thunderstorm potential for the plains and also
rainfall amounts, with generally light scattered showers expected.
The mountains will be better positioned to benefit from the
pattern, with orographic lift boosting precipitation and bringing
wetting rain to most of the high country, especially north of
I-70. Increased cloud cover will moderate temperatures somewhat,
though we should still break 80F in the lower elevations. The
southerly winds will be quite pronounced over the plains in the
afternoon with gusts 35-45 mph, resulting in elevated fire weather
conditions for any areas that receive little to no rain.

A pronounced closed low is set to dominate the Great Basin region
starting Wednesday and stalling into Thursday, feeding continued
moisture into our area as precipitation chances peak Wednesday
when afternoon showers and thunderstorms look to be most
widespread. Coverage should dwindle some on Thursday with higher
pressure in place over eastern Colorado. Friday into Saturday, the
low is progged to quickly lift NE through the Intermountain West
as it merges with the broader flow pattern. Warm surface
temperatures will continue, but with cooling air aloft, we should
see some better destabilization and thus favorable conditions for
afternoon thunderstorm development across much of the region.

&&

.AVIATION /12Z TAFS through 12Z Monday/...
Issued at 516 AM MDT Sun May 24 2026

VFR to prevailthrough the TAF period. South to southwest
drainage winds will continue at APA and DEN through 15Z. After
this, winds weaken with some modelsshowing them turning northwest
to northeast. While others just show light and variable
winds.Will go with light and variable winds through mid afternoon
(21Z), followed by northwest winds at DEN as outflow from
convection off to the west moves through. The threat for outflow
from high-based showers will continue into the early evening
02-03Z. Will go with a PROB30 for the showers and outflow wind
threat. Wind speeds from the outflows don`t look too strong,
reaching up to 30 knots.&&

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

&&

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

&&

$$

DISCUSSION...BRQ
AVIATION...12

NWS BOU Office Area Forecast Discussion