National Weather Service Forecast Discussion

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304
FXUS65 KBOU 161850
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
1250 PM MDT Thu Apr 16 2026

.KEY MESSAGES...

- Red Flag Warning continues due to critical fire weather
  conditions this afternoon and early evening for the southern
  and eastern forecast areas.

- Spring storm moves in overnight with snow of the forecast area
  and a much colder airmass.

- Hard freeze expected across the plains Friday night.

- Dry and warmer weather returns for early next week.

&&

.DISCUSSION /Through Thursday/...
Issued at 1243 PM MDT Thu Apr 16 2026

The rest of today will be warm and dry for all the forecast area.
The low humidities and gusty winds will keep the fire weather
conditions critical across the southern and eastern CWA into early
this evening. Temperatures are expected to reach the mid and
upper 70s across the plains for highs this afternoon.

Fairly dramatic changes to the weather are still on track starting
tonight.  Models are showing an upper trough to move eastward across
the state later tonight through Friday. A strong cold front will
move over the forecast area after midnight tonight with strong
northerly upslope winds behind it. Gusts up to 45 mph are possible
immediately behind the front.

Snow is expected for the forecast area, mostly on Friday, with
light snow lingering over the mountains into Friday night. The
best accumulations will be over the high mountains where up to 8
inches are possible through Friday night. The plains will see snow
too, but accumulations do not look significant. The latest model
runs now point to just 2 to 5 inches total over the foothills and
Palmer Ridge, and 1 or 2 inches, at best, over the western and
southern suburbs of greater Denver. The rest of the plains may see
an inch at best.

High temperatures will only reach the upper 30s to lower 40s across
the plains on Friday. With significant clearing expected Friday
night, readings will drop into the upper teens to mid 20s, so we
issued a Freeze Warning from 8 PM to 8 AM Saturday morning.

By Saturday, northwesterly flow aloft will push across the CWA,
then upper ridging moves in on Sunday. The airmass will warm a bit
on Saturday with highs in the 50s over the plains, then above
normal temperatures return on Sunday with highs in the 70s.

For the later days, Monday through Thursday of next week, upper
ridging is in place well into Wednesday with a dry airmass and
well above normal temperatures to continue.  By Thursday, models
are all over the place the next incoming upper trough, so confidence
is not very good just yet.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1146 AM MDT Thu Apr 16 2026

Per the previous discussion, under this southwest flow pattern,
it`s not unusual to see a shear zone develop, especially with
SCT/BKN high level clouds in the Denver area leading to
differential heating. South to southwest winds have decreased and
are expected to become variable at times after 18Z. The HRRR,
continues to show areas of light/VRB winds near and just north of
KDEN and KBJC this afternoon, therefore, we added a tempo for VRB
winds to the DEN TAF. KAPA will continue to see gusty southwest
winds up to 30 knots. Winds should start to relax again by 01Z-02Z
with the loss of daytime heating.

A strong front drops south across the area tonight, 05-07Z
bringing gusty north winds to around 35 knots. Winds will decrease
an hour or two after the front, with north to northeast winds at
10 to 20 knots through Friday. Low clouds develop behind the
front, closer to 12Z. Light to briefly moderate snow is expected
late Friday morning and early afternoon, roughly 15-20Z. Any
accumulation is expected to be light and confined to grassy and
elevated surfaces. MVFR conditions are expected for most of Friday
with occasional IFR conditions during the heavier snowfall. Snow
decreases and ends 20-23Z with skies clearing after 00Z Saturday.

&&

.FIRE WEATHER...
Issued at 1233 PM MDT Thu Apr 16 2026

We will keep the Red Flag Warning going for the southern and
eastern CWA the rest of the this afternoon and early evening due
to the 8-15 percent humidity levels and the 30 mph wind gusts.
Fuels remain extremely dry in these areas.
&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning until 9 PM MDT this evening for COZ214-216-241-
245>247-249.

Freeze Warning from 8 PM Friday to 8 AM MDT Saturday for
COZ038>051.

&&

$$

DISCUSSION...66
AVIATION...12
FIRE WEATHER...66

NWS BOU Office Area Forecast Discussion