National Weather Service Forecast Discussion

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379
FXUS65 KBOU 272001
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
201 PM MDT Fri Mar 27 2026

.KEY MESSAGES...


- Well above normal temperatures again for the weekend into early
  next week.

- Areas of elevated to locally critical fire weather conditions
  possible over the weekend and Monday.

- Pattern change by the mid to latter portions of next week, but
  highest chances of meaningful precipitation focused on the
  mountains.

&&

.DISCUSSION /Through Friday/...
Issued at 155 PM MDT Fri Mar 27 2026

Cooler temperatures behind the cold front finally makes it seem more
like spring than summer today. ACARS soundings still show mid-level
moisture sticking around across the plains. However, current visible
satellite imagery does show some erosion this past hour. At this
point, don`t think the low clouds will fully clear out before
sunset, so have slightly lowered max temperatures accordingly.

A surface high pressure will travel from the north to the central
Great Plains this afternoon and overnight tonight. Tightening of
pressure gradients will lead to gusty southerly winds today for the
Palmer Divide & eastern plains and into Saturday morning for the
eastern plains. Gusts up to 40-50 mph are possible at times before
gradually weakening by late Saturday morning.

Elevated-to-critical fire weather conditions are possible Saturday
afternoon as guidance is in good agreement relative humidity values
taking below 20% for the majority of the plains and foothills.
However, there is some uncertainty with strength and duration of the
winds. For the eastern plains, (particularly Lincoln and Washington
counties) the gusty southerly winds are progged to exit the area
before relative humidities dip below 15%. However, if the winds last
longer, fire weather highlights will be needed. For areas near South
Park and northern Front Range foothills, lee-troughing on Saturday
will result in breezy downslope winds. However, they should stay
below 25 mph, aside from brief 30-45 mph wind gusts. For these
reasons, have opted out of any fire weather highlights.

With the lee-troughing, some mid-level moisture will be advected
onto the plains. Isolated virga showers are possible (about 30%
chance) Saturday afternoon/evening as modeled Skew-T soundings show
elevated instability with high-based LCL`s. With any virga, gusty
outflows may occur as DCAPE values range between 600-1200 J/Kg.

Persistent upper level ridging will continue through Monday, once
again allowing warm air advection to bring above normal
temperatures (and possibly record-breaking temperatures,
particularly Sunday). The thermal ridge is progged to bring 700-mb
temperatures between +10 to +12 C, resulting in surface
temperatures in the high 70s to possibly even low 80s. The current
record for high temperature on Sunday, March 29 is 79 degrees
(current forecast is 80 degrees). With mostly dry conditions and
flat ridging leading to breezy downslope winds, elevated-to-
critical fire weather conditions are possible each day, with
highest concern being Monday due to breezier southwest winds
aloft.

Ensemble guidance continues to be in good agreement of a pattern
change mid-week next week. A shortwave trough will trek across the
northern U.S., with increasing southwest flow aloft advecting
moisture into Colorado. In this pattern regime, usually southwestern
Colorado will receive the best precipitation. However, the majority
of the GEFS and ECMWF ensemble solutions show measurable QPF for the
mountains. For the plains, it is more uncertain, with the GEFS being
slightly drier due to the track of the low. With a cold front
associated with the low expected, temperatures will likely be low
enough to support snow for the mountains, and possibly even
rain/snow mix for the plains. Stay tuned for more details!&&

&&

.AVIATION /18Z TAFS through 18Z Saturday/...
Issued at 200 PM MDT Fri Mar 27 2026

Model`s wind forecasts show brisk southeasterly winds at DIA this
afternoon, eventually getting due southerly early this evening. Will
keep the gusts to 30 knots going for late this afternoon through all
the evening. More normal, weaker drainage winds are expected by 08Z.
Concerning the Stratus deck, the latest VAD Wind Profile data is
showing that the cloud deck thinning but still around 3,000 thick.
Not certain when it will go to SCT.

&&

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

&&

$$

DISCUSSION...MAI
AVIATION...66

NWS BOU Office Area Forecast Discussion