National Weather Service Forecast Discussion

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084
FXUS65 KBOU 120541
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1141 PM MDT Mon May 11 2026

.KEY MESSAGES...

- Summerlike warmth and drier weather this week, with highs in the
  80s for the lower elevations.

- Warmest temperatures of the week (mid to upper 80s for the
  plains) on Wednesday and Thursday.

- A few afternoon showers and an isolated thunderstorm possible
  from Tuesday through Friday, mainly across the Front Range
  mountains and foothills.

&&

.DISCUSSION /Through Monday/...
Issued at 1213 PM MDT Mon May 11 2026

The well-advertised ridge across the southwestern CONUS is
gradually strengthening, leaving most of Colorado in a warm but
relatively quiet pattern over the next several days.

We`re well on track to seeing highs in the mid/upper 80s across
the plains today, with 12 PM temperatures already in the low 80s
at most locations. With dry air overhead (shown well by water
vapor satellite), only a few clouds are expected through afternoon
and evening hours.

A weak cold front is still expected to arrive sometime late
tonight or early on Tuesday. The front is expected to bring some
short-lived cooling (highs ~5-10F cooler than today), along with a
modest increase in moisture. Most guidance develops a narrow
corridor of instability across the Front Range during the
afternoon hours, and the weak upslope flow behind the front should
allow for a couple of weak showers and perhaps a brief
thunderstorm despite some capping.

Temperatures should quickly warm back up into mid/upper 80s by
Wednesday, with those well above normal temperatures continuing
into the weekend. Guidance has been slowing warming temperatures
on Wednesday, with ~30% of ECMWF ensemble members now getting DEN
to its first 90F high of the year. However, statistical guidance
remains a few degrees cooler and our current forecast is still
just under 90F for most locations. There is also a weak wave
working through the region Wednesday afternoon, with deeper
moisture aloft and better instability across most of the forecast
area. If we`re going to see any convection/measurable
precipitation this week, Wednesday afternoon would be the time to
do it.

Drier zonal flow by Thursday slowly transitions to southwesterly
flow aloft by the upcoming weekend. Guidance is generally in
better agreement handling the few 500mb shortwaves across western
North America in this time period, and generally keeps things
quite dry through the rest of the forecast period. The pattern
does look like it would turn a little more active by early next
week with a couple stronger shortwaves noted in today`s guidance.

&&

.AVIATION /06Z TAFS through 06Z Wednesday/...
Issued at 1133 PM MDT Mon May 11 2026

VFR conditions through the TAF period. Expect drainage winds to
continue at all terminals overnight, with APA becoming light and
VRB at times. Guidance indicates a slightly later time of arrival
with the cold front, closer to 11Z rather than 10Z. With the
passage of the front, expect winds to transition to the NE,
however stay below 15 kts.

For tomorrow easterly winds will take place, with winds
strengthening to 10-15 kts by 21Z. There is a low chance (

NWS BOU Office Area Forecast Discussion