National Weather Service Forecast Discussion

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473
FXUS65 KBOU 072033
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
133 PM MST Sat Mar 7 2026

.KEY MESSAGES...

- Warming trend returns this weekend, continues through
  Monday/Tuesday.

- Next chance for light precipitation Tuesday into Wednesday.

- Increasing winds and fire weather concerns possible for the
  second half of the week.

&&

.DISCUSSION /Through Saturday/...
Issued at 1259 PM MST Sat Mar 7 2026

Upper-air maps show a positively tilted trough stretching from the
southwestern US to the Midwest this morning that has begun to
close off over SoCal. Models are in large agreement that this will
continue to spin off the west coast of Baja/SoCal through the
weekend, with upper level ridging taking hold across the western
US as the low cuts off under the ridge. Satellite imagery shows
yesterday`s snow-maker left a blanket of white across the majority
of the forecast area, which is a welcome change after February
ending as one of the warmest and driest on record. A gradual
warmup is expected through the weekend as the current northerly
flow aloft becomes more zonal with multiple shortwaves moving
across the northern tier of the US.

For the rest of today and tonight, dry conditions are expected
across the forecast area, with mostly clear skies under subsident
flow aloft. Recent snowfall will see some melting today as temps
warm into the 40s and low 50s through the afternoon. This could make
for some slick conditions tonight with below freezing temps expected
and refreezing possible on untreated roads and sidewalks. With clear
skies expected overnight and the recent snowfall, trended overnight
lows in our mountain valley`s a few degrees lower than the previous
forecast.

700 mb temps should see around a 12C warming for Sunday afternoon
that will translate to the return of above-normal surface
temperatures across a majority of the forecast area. Mild and dry
conditions will accompany an extra hour of daylight with the time
change.

Zonal flow will start to increase on Monday as the aforementioned
southwest low begins to move eastward and colder air starts to usher
into the northern US. Temperatures will remain above-normal
across the forecast area, with no precipitation expected once
again. Patches of elevated to critical fire weather conditions
will start to enter the picture Monday afternoon with the
persistent warm and dry conditions. Relative humidity values start
to drop to near or just below critical thresholds in areas where
the latest snowfall was minimal or missed out on completely. As on
now, winds look to remain below critical thresholds where the RH
values are at their lowest, but there may be a few hours of
elevated to critical fire weather conditions over southern Lincoln
County where current satellite imagery shows no snowfall on the
ground.

On Tuesday, the closed low is progged to get re-absorbed into the
main flow as it crosses the southern Rockies and a shortwave skirts
just to the north of Colorado. The forecast area will reside just
outside of the main QG forcings (sandwiched in the middle), but
mid-level moisture will increase enough to bring some light
mountain snow showers, and a cold front with modest frontogenesis
is expected to slide south across the forecast area by Tuesday
evening that could see some light precipitation develop across the
plains. As mentioned in the previous discussion, the GFS and
ECMWF ensembles continue to show some slight discrepancies with
QPF totals, but at least a few of the GFS members show light
precip along the northern and southern borders of our CWA (keeping
the majority of the forecast area dry), with the ECMWF still
holding onto at least a few hundredths possible across the plains,
with slightly higher amounts for the northern and central
mountains.

Cooler temps and drier conditions are expected on Wednesday
behind the cold front. Ridging rebuilds over the western CONUS
through the day, with well above-normal temperatures returning
for the second half of the week. By Thursday, along with the
warmer temperatures, a tightening pressure gradient will bring
stronger winds to much of the forecast area that will increase
fire weather concerns.



&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1038 AM MST Sat Mar 7 2026

VFR through the TAF period. With a deep snowpack across the
southeastern metro, drainage winds are likely to persist today and
tonight for DEN/APA, with slightly more variable winds at BJC. No
ceiling or visibility concerns through Sunday.

&&

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

&&

$$

DISCUSSION...9
AVIATION...Hiris

NWS BOU Office Area Forecast Discussion