National Weather Service Forecast Discussion

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247
FXUS65 KBOU 071939
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
139 PM MDT Tue Apr 7 2026

.KEY MESSAGES...

- Isolated to scattered showers this afternoon. Precip amounts
  will be low. Potential for gusty winds due to virga near
  showers.

- Elevated to fire weather conditions over the plains, foothills
  and mountains parks Wednesday afternoon.

- Higher chances for afternoon precip (25-60%) across much of the
  forecast area both Thursday and Friday.

- Unsettled weather pattern Saturday through Tuesday with decent
  chances of precipitation across the CWA.

&&

.DISCUSSION /Through Tuesday/...
Issued at 113 PM MDT Tue Apr 7 2026

Cumulus clouds are forming over the mountains and Foothills as of
early this afternoon and are pushing off into the plains.
Unfortunately, conditions are very dry across the plains with
dewpoint depressions around 30 to 45 degrees across much of the
area. This will limit precip amounts and increase the potential
for gusty winds from virga and possibly dry microbursts. Based on
current and forecast DCAPEs this afternoon, wind gusts could be
around 30 to 40mph near any dry microbursts that form. There is a
low chance for lightning as well with the activity this afternoon,
with the best chance for thunderstorms in our southern counties
near the Palmer Divide and South Park. Precip chances will lower
around sunset.

Conditions are expected to remain mostly dry tomorrow, with a low
potential for isolated showers and thunderstorms. Once again,
there is going to be a wide spread between the dewpoint and
temperature at the surface, leading to the potential for gusty
winds around 30 to 40mph with any activity that develops. Winds
on Wednesday are a bit tricky. A 50kt 700mb jet is forecast to sit
near the CO/WY border Wednesday morning. Winds at mountain top
will gust around that 50kt value for a few hours, but winds on
the plains are more uncertain. Mountain wave enhancement is not
expected with this event, the atmosphere just looks a little too
unstable. However, mixing could still bring some breezier winds
down to the surface across the plains. Some models are mixing
gusts of around 30 mph towards the surface in the Foothills and
adjacent plains. This typically wouldn`t be of much concern, but
with the dry conditions we`re expecting, these stronger winds
would lead to critical fire weather concerns. Another potential
wrench in the winds is the cold front Wednesday morning and
afternoon. If the cold front is a bit faster, it will cut off
those stronger winds aloft, leading to weaker NE winds rather than
gusty W/NW winds during the time of minimum RHs. We`ll hold off
on any fire weather products for now due to the uncertainty, but
we`ll have to keep a close eye on the mixing potential and front
for tomorrow.

Precip chances start to increase on Thursday, with an active pattern
expected this weekend and early next week. Moisture will continue to
increase Thursday into Saturday, with PWATs reaching ~200% of normal
Friday night into Saturday morning. A cold front will to move into
the area later on Thursday afternoon. The added moisture and weak
surface convergence along the front could be enough to trigger some
scattered showers and maybe a few thunderstorms late Thursday
afternoon into Thursday evening. Once again, we`re not expecting
any widespread rainfall, but some areas could see up to a tenth of
an inch of rain, with most areas seeing nothing to a few
hundredths. An upper level low will sit off the west coast of the
United States through Saturday, putting us in southwest flow
aloft. Little upper level disturbances and additional moisture
will move through this flow aloft, bringing additional rain
chances for Friday and Saturday. Precip amounts look a little more
promising during this time, due to those higher PWATs and
potentially convective nature of some of the activity, but much
of the area is still sitting around a few hundredths for each
round, with higher amounts in more localized areas under storms.
For the mountains, expect on and off snow showers each afternoon
through the end of the week for locations above 8500ft to 9000ft.
Snow amounts will remain low, with much of the mountains staying
below an inch or two of snow through Friday.

Sunday into early next week holds a lot of uncertainty. Small
changes in the potential upper level pattern will have big impacts
in our area. And with the models changing between each run, we
have little confidence in any one model solution. There is
potential for a more potent shortwave to move through sometime
late Saturday or Sunday. If this shortwave moves over our area, it
will provide decent lift and better precip chances. However, some
runs have a much less potent shortwave that moves to our west and
north, which would not be as beneficial for precipitation in our
area. The next system looks a bit more interesting with the
potential for an upper low to approach and move through Colorado
early next week. However, this far out, models can change
significantly in both track and intensity of systems like this.
Looking at model ensembles and NBM probabilities, right now we`re
looking at a low chance (~30%) of much cooler temperatures, more
significant precipitation amounts, and potentially even snow
across the plains early next week.

&&

.AVIATION /18Z TAFS through 18Z Wednesday/...
Issued at 1210 PM MDT Tue Apr 7 2026

Winds are currently light and variable across the region with
more of an E-SE component early this afternoon. We have low
confidence in wind direction through early this evening given that
the prevailing speed is expected to remain light, and some high-
res models are still suggesting a cyclone developing near the
southeastern Denver metro area, which would impact wind direction
at all three airports. Another point of uncertainty this afternoon
is the possibility (30% chance) of downbursts caused by nearby
high-based showers or virga, which would lead to periods of wind
gusts up to 25-30KT around 22Z-02Z.

Otherwise, winds will transition to the usual southwesterly
drainage flow tonight through early Wednesday morning. A brief
period of W-NW breeziness is expected tomorrow with a few gusts up
to 25KT at KBJC and KDEN before a northerly push arrives around
21Z ahead of a cold front. High clouds will be in place through
the end of the forecast period and low ceilings are not a concern.

&&

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

&&

$$

DISCUSSION...AP
AVIATION...AA

NWS BOU Office Area Forecast Discussion