National Weather Service Forecast Discussion

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247
FXUS65 KBOU 140842
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
242 AM MDT Thu May 14 2026

.KEY MESSAGES...

- Summerlike warmth through Friday with isolated high based
  showers and thunderstorms.

- Elevated to locally critical fire weather conditions each day
  through Friday.

- Shower and storm chances will increase this weekend into early
  next week. Trends have been wetter and cooler, especially by
  late Sunday and Monday.

&&

.DISCUSSION /Through Wednesday/...
Issued at 236 AM MDT Thu May 14 2026

Current water vapor satellite imagery shows an upper level shortwave
in Montana. As this system treks east today, flow aloft will turn
more westerly over Colorado with the ridge flattening. Models
indicate cross-barrier flow of 30-40 kts, mainly for northern
Colorado. Modeled Skew-T soundings show mixing heights around
10,000 ft, which will allow gusty winds to mix down to the
surface. With relative humidity values expected to drop to 8-13%
in the afternoon, elevated to critical fire weather conditions are
likely for our northern plains where fuels have recently been
deemed critical. A Red Flag Warning is in effect from 11 AM to 9
PM today for those areas. Portions of the northern mountains and
foothills may see localized elevated fire weather conditions,
however recent green- up will keep concerns from being widespread.

It will be another warm day across the forecast area despite
"cooler" air being advected into the region as the mid-level thermal
ridge shifts east of Colorado. Most of the plains will see
temperatures in the high 80s (and possibly low 90s in the eastern
plains). Most guidance keeps KDEN from tying/breaking the record
high temperature today (Forecast: 86F, Record: 87 set in 2013).
However, compressional heating from west/northwest winds in the
afternoon could warm us up slightly more.

Most of the forecast area should remain dry today. However, with
lingering mid-level moisture, we could see an isolated afternoon
shower/storm for the southern foothills and Palmer Divide area.
Gusty outflows will be the main threat if this occurs, given
DCAPE values of 1000-1300 J/kg.

Above normal temperatures likely on Friday, with highs reaching up
to the 80s again across the plains. Should be a mostly quiet day,
with a low chance (~20% chance) for weak afternoon virga
showers/thunderstorms, mainly for the southern portion of our
forecast area.

Temperatures should still be above normal over the weekend, however
model guidance has been trending cooler due to ensembles resolving
a stronger incoming upper level trough. There is still a bit of a
spread in max temperatures, especially for Saturday, but
confidence is increasing of highs in the upper 70s, rather than
the 80s as previously advertised. With a stronger upper level
trough, confidence is increasing of the forecast area seeing
better shower/thunderstorm coverage, with measurable precipitation
(including snow for elevations above 9,500-10,000 ft!) on Sunday
and especially on Monday. Some uncertainty with temperatures on
Monday, as deterministic GFS/ECMWF and their AI counterparts
showing 700 mb temperatures anywhere from -4C to 4C. This is
resulting in a large spread of max temperatures in ensemble
guidance. However, temperatures are likely to range between high
50s to low 60s across the plains for Monday and Tuesday, which
will be a nice reprieve from the heat we have been seeing.

&&

.AVIATION /06Z TAFS through 06Z Friday/...
Issued at 1135 PM MDT Wed May 13 2026

VFR conditions expected through the TAF period. Aside from an
outflow boundary moving through DEN and BJC (allowing westerly
winds up to 20 kts), drainage flow is taking place and will
continue overnight. Some uncertainty with wind direction behind
the outflow at DEN, with the potential of westerly winds staying
in place for the next hour or so before drainage flow can return.

For tomorrow, drainage flow will transition to northwest winds by
late morning to early afternoon (between 17Z and 21Z), with
speeds up to 15-20 kts at times. By the evening, expect a typical
diurnal wind pattern, with winds gradually turning to drainage by
05Z/06Z.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM this morning to 9 PM MDT this
evening for COZ238-242-248-250-251.

&&

$$

DISCUSSION...MAI
AVIATION...MAI

NWS BOU Office Area Forecast Discussion