375
FXUS65 KBOU 021908
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
108 PM MDT Sun Aug 2 2026

.KEY MESSAGES...

- Heat turns up today, with temperatures reaching into the upper
  90s and lower 100s this afternoon and again on Monday.

- Heat Advisory in effect for the I-25 corridor and Weld County from
  this afternoon through Monday evening.

- Elevated fire weather conditions are expected across the eastern
  plains this afternoon.

- Cooler for Tuesday and Wednesday.

&&

.DISCUSSION /Through Sunday/...
Issued at 1247 PM MDT Sun Aug 2 2026

Temperatures this afternoon are already in the upper 90s to lower
100s across the I-25 corridor and northern plains. The Heat
Advisory began at noon today and will go into tomorrow afternoon.
Overnight temperatures will remain well above normal tonight,
potentially reaching record-breaking values (if the front doesn`t
drop temperatures below the morning low in the evening tomorrow).
The current forecast low for Denver tomorrow morning is 71
degrees and the record warmest low for tomorrow`s date is 68
degrees, set in 1981.

The high temperature forecast for tomorrow still has quite a bit of
uncertainty for our northern plains counties. The thermal ridge
will remain over the area, with anomalously warm 700mb
temperatures. Models are still struggling with the timing and
strength of tomorrow`s cold front, changing the time it enters our
forecast area from the north by as much as 6 hours from run to
run. If the front ends up moving into the area prior to peak
heating, highs in our northern counties could be significantly
reduced, and northern portions of our Heat Advisory could remain
below Heat Advisory criteria. However, if the front takes on the
slower approach, temperatures could reach into the upper 90s to
lower 100s range for our northern counties. Confidence increases
in our high temperature forecast the further south we go,
including the urban corridor. Right now, we`re going to leave the
spatial extent of the Heat Advisory the same, but we did trim off
a few hours at the end of the Advisory to account for the cooling
behind the front.

Now for the precip side of things tomorrow. There is a low chance
(~20% to 30%) that the front could trigger some convective
activity tomorrow afternoon. Lower levels however will be very
dry, so if the surface convergence and upslope from the
northeasterly winds can trigger some activity, rain may not
actually be able to get to the surface before evaporating. Which
means we could be dealing with some strong, gusty winds due to
virga and DCAPEs around 1300 to 2000 J/kg in the afternoon. We`ll
also have to be on the lookout for spotty critical fire weather
conditions tomorrow. Relative humidities will be low ahead of the
front, with some recovery behind it. However, the gusty winds
associated with the front could overlap with the low RHs for an
hour or two before the RHs can recover enough to get out of those
critical thresholds. No RFW will be issued at this time due to
the spotty nature of the critical conditions, in both time and
space, but it is something to be cautious of.

Temperatures will be cooler behind this frontal system for
Tuesday and Wednesday. The strength of the front is till a bit up
in the air, but the good news (for those tired of the heat), is
that the NBM 25th to 75th percentile for highs on Tuesday generally
ranges from the mid 70s to mid 80s in the plains. So, confidence
is pretty high that temperatures will be at least 15 degrees
cooler for much of the plains on Tuesday, if not closer to 25
degrees cooler. The mountains won`t be as lucky however. The
front will have a smaller impact in the higher terrain, as that
thermal ridge lurks off to our west. Models are showing a
disturbance moving through the flow aloft Tuesday
afternoon/evening. This disturbance and easterly, upslope surface
winds could be enough to trigger some convection. Models are
showing some mid level capping, which could prevent any strong
storms from developing. But, if we can get over the cap,
strengthening mid level winds will allow for decent wind shear and
the potential for stronger storms.

Temperatures will gradually warm each afternoon into the weekend,
with highs reaching into the triple digits by Friday or Saturday for
portions of the plains. Precipitation chances will decrease as we go
into the end of the work week and start of the weekend, as the upper
level high builds back over the area and large scale subsidence
takes over once again.

&&

.AVIATION /18Z TAFS through 18Z Monday/...
Issued at 1140 AM MDT Sun Aug 2 2026

VFR conditions are expected through at least Monday afternoon.
Only few to sct mid and upper-level clouds are expected through
at least Monday afternoon. Winds are currently vrb and should
slowly become prevailing easterly later this afternoon. Late this
evening and overnight through about 09z, strong drainage winds are
forecast with some gusts around 25 kts at KDEN and KAPA and a
TEMPO for this possibility at KBJC. Otherwise, winds will follow
the typical diurnal pattern and then turn to NW/NNW tomorrow
afternoon. There is the possibility of stronger winds tomorrow
afternoon shown across numerous CAMs ahead of an incoming cold
front. We have introduced a PROB30 for tomorrow afternoon for the
possibility of showers causing gusty outflow winds and lowering
clouds at the terminals as well.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 6 PM MDT Monday for COZ038>043.

&&

$$

DISCUSSION...AP
AVIATION...MV

NWS BOU Office Area Forecast Discussion