580
FXUS65 KBOU 092050
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
250 PM MDT Sun Mar 9 2025

.KEY MESSAGES...

- Dry weather through Thursday. Monday the warmest day, when highs
  push to 70F or more across the plains and I-25 Corridor.

- Critical fire weather conditions expected for the northern
  plains Monday, with elevated conditions near the foothills and
  South Park. Localized elevated fire weather conditions across
  the plains mid/late week too.

- Still watching the potential for a potent, quick moving storm
  system late this week, with a variety of impacts possible.

&&

.SHORT TERM /Through Monday/...
Issued at 250 PM MDT Sun Mar 9 2025

Spring-like warmth will continue through Monday as an upper level
ridge shifts east. The flow aloft strengthens as today`s shortwave
moving into the Pacific Northwest moves across the Northern
Rockies. This spells increasing winds and fire danger to the
forecast area, details on that in the fire weather section below.

We`ll have further warm advection tonight, keeping low temperatures
rather mild in/near the foothills. Some weak cold advection aloft
arrives tomorrow afternoon due to the shortwave to our north, but
that will be offset by enhanced downslope flow. Therefore, we
still expect high temperatures to reach the lower 70s across most
of the plains, with even mid 70s over the lowest elevations. One
thing that may hold highs back a degree or two would be increasing
high clouds, as some models have a little thicker of a wave cloud
near the Front Range. Overall, we don`t think it`ll have much of
an impact. Regarding winds and a well mixed airmass, we expect
wind gusts to mostly range from 15-25 mph over the plains during
the late morning and afternoon, with gusts 25-30 mph over the
northern border, 30-50 mph in/near the wind prone areas of the
foothills, and up to 50-60 mph over the highest Front Range Peaks.

&&

.LONG TERM /Monday night through Sunday/...
Issued at 250 PM MDT Sun Mar 9 2025

Slightly cooler, although still above normal temperatures are
expected on Tuesday due to cold air advection from a backdoor cold
front. Most of the plains will reach up to the mid 60s and wind
gusts up to 30 mph are possible across the eastern plains.

The upper level ridge will break down as a weak shortwave trough
traverses New Mexico on Wednesday into Thursday. However, this
system will be too far south to have any impacts for us. Aside from
localized fire weather conditions across the plains (see fire
weather discussion) relatively quiet weather with above normal
temperatures are expected through Thursday.

Ensemble guidance has continued to favor a strong, but fast
moving system traversing the area on Friday and ejecting into the
Central Plains. This system will bring very strong winds to the
high plains, with recent guidance indicating the northern counties
reaching high wind criteria. It is likely (~60% chance) that wind
gusts could exceed 60 mph by late Friday. However, there is still
a lot of uncertainty with this storm precipitation-wise. Due to
how fast this system will move, the time window for precipitation
will be limited. In addition, temperatures may be too warm
initially to support snowfall. So the question is- will the rain
transition to snow in time for measurable snowfall in the plains?
As of right now, that is not looking likely. There is a 15-20% of
snow accumulation greater than 2", although there are still a few
ensemble members favoring higher snowfall total. If we start
seeing cold air being pulled into our area sooner, confidence will
increase on higher snowfall totals. Regardless, even if the
plains get an inch or two of snow, the very strong winds could
produce some localized whiteout conditions. We will continue to
monitor!

&&

.AVIATION /18Z TAFS through 18Z Monday/...
Issued at 1143 AM MDT Sun Mar 9 2025

VFR will persist with only FEW-SCT high cirrus. Winds will
gradually transition to VRB or light easterly by 21Z, only to
return to normal south/southwest drainage winds around 8-12 kts by
03Z. Those winds should start to trend more westerly by 16-17Z
Monday, with potential gusts to 20-25 kts by 18Z at KBJC, and
closer to 20Z at KDEN and KAPA. Given lack of forcing, appears the
gustier west winds may end up in channels, with not all locations
seeing them Monday afternoon.

&&

.FIRE WEATHER...
Issued at 250 PM MDT Sun Mar 9 2025

Monday will be warm across the forecast area, with high
temperatures ranging from 12-20 degrees above normal. In
addition, the airmass will be very dry, with minimum RH of 6-12%
across the plains, lower foothills, and South Park. Critical fire
weather conditions are expected to develop over the northern
border area given stronger flow there and gusts to 25-30 mph
during the late morning and afternoon hours. We`ve issued a Red
Flag Warning for those northern plains zones.  We are also
concerned about South Park, where a check with local land managers
suggest patchy snow cover in the forested areas (more on
north/east facing slopes), so we`ll forgo any highlight here for
the time being. Still something to watch though for the grasslands
of South Park.

Localized elevated fire weather conditions are possible for the
northern plains on Wednesday and southern plains/Palmer Divide on
Thursday. Temperatures will be 10-15 degrees above normal with
relative humidity values reaching down to 15% and wind gusts up
to 25 mph. Due to these conditions being fairly localized and
brief, no highlights are expected at this time.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning from 11 AM to 7 PM MDT Monday for COZ238-242-
248-250-251.

&&

$$

SHORT TERM...Barjenbruch
LONG TERM...Ideker
AVIATION...Barjenbruch
FIRE WEATHER...Barjenbruch