National Weather Service Forecast Discussion

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858
FXUS65 KBOU 131811
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1211 PM MDT Sat Jun 13 2026

.KEY MESSAGES...

- Elevated to near critical fire weather conditions possible today
  across the high country.

- Cooler temperatures today and Sunday behind a cold front.

- The best chances for showers/thunderstorms will be Sunday.

- Temperatures heat back up next week.

&&

.DISCUSSION /Through Friday/...
Issued at 215 AM MDT Sat Jun 13 2026

An early morning cold front will bring cooler temperatures to the
forecast area today along with gusty northeasterly winds, and an
increase in low-level moisture. Afternoon temperatures are forecast
to warm into the upper 70s to low 80s across our lower elevations
and mountain valleys. The increasing moisture will help suppress
any critical fire weather conditions across the lower elevations,
but with the moisture not expected to push into the higher
elevations, we will still see some elevated fire weather
conditions for our mountain valleys where relative humidities are
still expected to drop into the low to mid teens this afternoon.
A secondary surge of northeasterlies are expected later this
afternoon that will enhance upslope flow and precipitation chances
for the afternoon and evening. Precipitation will primarily be
limited to our Central Mountains, southern foothills, and the
Palmer Divide, where we could see a few weak thunderstorms and
showers develop, with low chances of these holding together as
they move off the higher terrain. With the persistent
northeasterlies in place, we could see some smoke start to filter
into the region from fires burning in eastern Wyoming and western
Nebraska. The greatest concentrations look to make their way into
the area late tonight/early Sunday morning, settling up against
the Front Range and urban corridor by sunrise Sunday.

Much cooler temps are expected Sunday behind today`s cold front,
with well-below normal high temps in the 60s forecast for the
lower elevations. Ensembles show PWATs increasing to around
130-140% of normal for the Central Mountains and Palmer Divide
where up to 500 J/kg of MLCAPE and a passing shortwave will
provide enough support for some afternoon thunderstorms that will
be our best shot for precipitation for the week. QPF will be
greatest along the Palmer Divide where a few tenths will be
possible with any storms that develop, with only a few hundredths
possible elsewhere across the lower elevations.

Temperatures will start to increase again on Monday as Colorado will
be on the eastern side of a building upper-level ridge over the
western CONUS. Ensembles show a significant decrease in PWATs
through the forecast period and a steady increase to temperatures
through midweek, where they are looking to peak on Wednesday before
another cold front slides south across the area sometime Wednesday
night. PoPs are minimal to nonexistent after Monday and with
above normal temps expected, we will have to start monitoring for
critical fire weather conditions developing as fuels start to dry
out.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1205 PM MDT Sat Jun 13 2026

Winds are currently NNE with a few gusts up to 20KT being
observed. Some stronger (25-30KT) gusts will be possible with a
reinforcement of the NE winds between 23Z and 02Z, as well as an
isolated shower. The shower potential this evening still looks to
be rather low (

NWS BOU Office Area Forecast Discussion