National Weather Service Forecast Discussion

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863
FXUS65 KBOU 091935
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
135 PM MDT Sat May 9 2026

.KEY MESSAGES...

- Scattered afternoon and evening showers/thunderstorms likely for
  the northeastern plains this afternoon and evening.

- Summerlike warmth and drier weather next week, with highs in the
  80s for the lower elevations.

&&

.DISCUSSION /Through Saturday/...
Issued at 134 PM MDT Sat May 9 2026

Latest satellite imagery shows the shortwave of interest for today
moving through Montana and Wyoming with cumulus clouds developing
across eastern WY. Today will be a bit warmer than yesterday with
highs generally in the mid 70s across the plains. A few showers and
thunderstorms are expected for this afternoon, especially for the
northeast plains, starting around 3pm. These showers/thunderstorms
will be associated with the aforementioned mid-level shortwave
embedded in the northwest flow aloft as it moves across NE CO. DCAPE
values are expected to be between 1000 and 1300 J/kg this afternoon,
meaning any stronger storms could produce gusty outflow winds. A low
risk for small hail also exists for the northeast plains given
strong shear and modest instability in place as noted in model
soundings. These areas are in a marginal (1/5) risk for severe
storms.

The precipitation chances will transition southward throughout the
evening as a cold front moves through the forecast area, but storms
should decrease in coverage and intensity with the loss of daytime
heating as they approach the Denver metro. The highest chances for
showers in the Denver metro - between 30 and 40 percent - will be
between 10pm and 2am tonight. Wind gusts could briefly reach 35 to
45 mph as the cold front passes through. Despite tonight`s cold
front, warm air advection should allow high temperatures on Sunday
across the plains to return to the upper 60s and low 70s.

A strong ridge of high pressure is still on track to setup near or
over our forecast area for most of next week leading to well above-
average temperatures through the rest of the forecast period. Highs
for the work week will be in the mid to upper 80s for the plains
with the northeast plains even having the possibility of reaching
the low 90s during the middle of week. The hottest temperatures of
the week are expected on Wednesday when the ridge is at its
strongest. As noted in the previous discussion, the record high for
Denver is 90 degrees F and we have an outside chance of tying or
breaking that record. Precipitation chances could increase again by
the end of the week, but there is disagreement among the global
models on the evolution of a potential shortwave pivoting into
Colorado. Elevated to critical fire weather conditions are possible
through the week given the dry conditions, but there is quite a bit
of uncertainty with how much wind there will be on any given
afternoon.

&&

.AVIATION /18Z TAFS through 18Z Sunday/...
Issued at 1207 PM MDT Sat May 9 2026

Models are generally showing NW to NNE wind directions at DIA
through the afternoon. Gusts to 25 knot look to be as strong as
they will get. The advertised cold front looks to arrive at DIA
around 00Z. Wind gusts behind the cold front could reach 35 knots.
I will leave the TS out for now with the best instability well
north of DIA. Once the front passes, the precipitation will be
more Stratiform in nature.  So far as ceilings go, will get them
down into the BKN-OVC010-025 range after 03z, with a TEMPO group
down to BKN005 along with -RA. Ceiling will improve by 12Z-13Z.

&&

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

&&

$$

DISCUSSION...MV
AVIATION...66

NWS BOU Office Area Forecast Discussion