National Weather Service Forecast Discussion

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387
FXUS65 KBOU 040527
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1127 PM MDT Fri Apr 3 2026

.KEY MESSAGES...

- Scattered light snow showers in the mountains will come to an
  end tonight.

- Breezy with elevated fire weather conditions for the northeast
  plains Saturday. Lighter winds elsewhere including the I-25
  Urban Corridor.

- Dry with a gradual warming trend through the middle of next week
  (outside of Monday). Elevated to critical fire weather
  conditions likely return by Wednesday (60% chance).

- Unsettled weather returns for the end of next week.

&&

.DISCUSSION /Through Friday/...
Issued at 1127 PM MDT Fri Apr 3 2026

A fairly quiet weather pattern can be expected for the next few
days with dry weather through the weekend. Any lingering snow
showers in the high country will be ending tonight, with perhaps
just a few flurries into Saturday morning stuck over the highest
peaks. The incoming dry weather will be courtesy of a flat upper
level ridge that shifts ever so slowly eastward from the Great
Basin across Colorado through Monday. This means a persistent dry
W-NW flow aloft, and weakening flow aloft which also means less
wind.

That said, for Saturday, it will still be breezy across the
eastern plains due to modest gradients in the wake of the most
recent storm system moving toward the Great Lakes. However,
humidity readings will be improved slightly from those observed
Friday so no fire weather highlights will be needed. Meanwhile,
much lighter winds can be expected along the I-25 Urban Corridor
with a shallow anticyclone developing. Temperatures will be
warming to near seasonal normals with sunny skies and just slight
warming aloft.

We expect further warming to above normal readings for Sunday,
with good agreement that we reach the mid to upper 60s over most
of the plains. Models continue to support a backdoor cold front
arriving late Sunday or Monday morning. It was interesting to note
the EPS runs were still averaging nearly 10 degrees warmer than
the GEFS for Monday`s highs. Even the typically cooler EC-AIFS
was warmer than GEFS. However, in the case of backdoor cold
fronts we typically prefer the slightly cooler output and lean
toward the GEFS.

Tuesday is shaping up to be warmer again, as any cooling by the
backdoor cold front will eroding to the east. Breezy west winds
will develop over the high country. With regard to precipitation
chances, models still show some mid level moisture increasing and
potential for a weak shortwave. However, the zonal flow aloft
should keep any convection quite weak and scattered in nature.

The warmest day of the week will likely be Wednesday as afternoon
highs on the plains climb into the low to mid 70`s under strong
westerly flow at the upper levels. Wednesday will also have the
potential for widespread breezy conditions as steep lapse rates
allow higher wind speeds aloft to mix down to the surface, in
addition to downsloping winds in the Foothills. While it is a bit
early to tell, ensemble model guidance suggests low relatively
humidities (10-20%) will also be in place Wednesday afternoon
giving way to elevated or critical fire weather conditions.

A cold frontal passage will occur sometime late Wednesday evening
into Thursday morning and kick off a more active and cooler
weather pattern that will persist through the weekend. A plume of
Pacific moisture will bring increased PWATs, a chance for
mountain snow, and perhaps a few sprinkles for the the lower
elevations on Thursday. Friday will likely see the best chance
for rain showers over the northeastern and central plains of
Colorado.

&&

.AVIATION /00Z TAFS through 00Z Sunday/...
Issued at 551 PM MDT Fri Apr 3 2026

Model show the strong west-northwesterly winds at DIA to decrease
substantially by 02Z, with a brief period of much weaker
northerly winds, before weak drainage patterns kick in after
midnight around 08Z. There will be no ceiling issues.

&&

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

&&

$$

DISCUSSION...20/AA
AVIATION...66

NWS BOU Office Area Forecast Discussion