534
FXUS65 KBOU 101138
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
538 AM MDT Fri Apr 10 2026

.KEY MESSAGES...

- A brief cool down today with scattered rain showers. Isolated
  thunderstorms will also be possible over the higher terrain and
  portions of the I-25 Corridor.

- Scattered showersSaturday with a few thunderstorms, mainly
  over the mountains andfar northeast plains.

- Warm and dry Sunday and Monday, with breezy/windy conditions
  possible along with increasing fire conditions.

&&

.DISCUSSION /Through Thursday/...
Issued at 1051 PM MDT Thu Apr 9 2026

SW flow aloft will be over the area today with southeast low level
flow across the plains.  Expect a decent Denver cyclone to develop
although not sure exactly where it will be located.  Initial
thoughts would be to have it over nrn Douglas county. There will
be a convergence zone associated with it which may act as a focus
for tstm development late in the aftn into the early evening
hours. MLCAPE up to 500 j/kg will develop along and south of the
boundary in the aftn. If convective temps can be reached then may
see a few stronger storms with a weak landspout or two possible
along the boundary. Temps will be a problem as readings to the
north and west of the Denver cyclone will be cooler than south and
southeast of the cyclone. Thus have modified readings to account
for this. Over the plains, stratus may hold thru much of the aftn
which may keep highs in the upper 40`s to lower 50s. Over the
higher terrain will see a chc of aftn showers and tstms.

For Sat, SW flow aloft will remain in place.  Cross-sections show an
increase in moisture over the higher terrain with favorable lapse
rates. As a result, will see a good chc of showers and a few
tstms. Across the plains, the low level flow will be SSW with
best moisture confined to the far nern plains, where SBCAPE may
be up to 1000 j/kg. Thus will see a chc of high based showers and
a few storms in the aftn, with a few stronger storms, possible
over the far nern plains. Highs will be warmer with readings in
the 70`s over the plains.

By Sun, drier air in SW flow aloft will spread over the area with
little chc for pcpn.  Temperatures will remain warm across the
plains with increasing wind over the higher terrain and portions of
the plains.

On Mon, an upper level trough will move into the Great Basin with
stg SW flow aloft.  Meanwhile, sfc low pres will be located across
the plains.  Overall, it looks like another day of mainly dry
weather across the plains with above normal temps and gusty winds.
Over the mtns, latest data suggest best chc for showers and a few
tstms will be Mon night and not during the aftn. In addition,
expect windy conditions as well.

By Tue, there is still a lot of disagreement as to the track of an
upper level low.  The ECMWF has it now moving across WY while the
GFS has an open wave trough affecting the area.  For now, it appears
best chc of precip will be over the mtns with quite a bit of
uncertainty across the plains.

For mid week, the flow aloft will become more westerly which will
lead to a drier pattern along with warmer temperatures.

&&

.AVIATION /12Z TAFS through 12Z Saturday/...
Issued at 538 AM MDT Fri Apr 10 2026

Main concerns surround a threat of stratus and lower IFR/MVFR
ceilings this morning, and then scattered showers and isolated
storms with variable winds late this afternoon/early evening.

A weak and shallow upslope flow behind last evening`s front is
supporting some stratus development over the eastern plains toward
Limon as of 1130Z, spreading northwest. At the current speed (and
barring any expansion), the western edge would get close to KDEN
toward 1330Z. However, there`s southerly flow just off the deck
and a downslope component off the Palmer Divide, so we think the
chance of an IFR or MVFR ceiling is now about 40-50% at KDEN
between 14Z and 16Z. Still something to watch closely. Odds would
be lower (10-25%) at KBJC and KAPA.

Otherwise, the main concern will shift to the development of a
Denver Convergence Vorticity Zone (DCVZ). The exact location and
movement of this feature will determine how winds evolve through
the day. At this time, we have growing confidence (near 80%) that
the cyclone will be developing and moving south of KDEN which
means E-NE winds should develop and hold through most of the day,
before becoming NW or VRB once convection develops in the area.
That cyclone and associated convergence will also be the main
driver of convective initiation, but appears to be a rather late
day with most shower/storm development holding off til 22Z-01Z.
We`ll keep the TEMPO -TSRA in the forecast for that period of
highest confidence, and also mention VRB gusts to 25-30kts.

Convective activity is mostly agreed upon to move east and exit
the area by 02Z. Then winds should settle down and return to
slightly enhanced south/southwest winds by 04-07Z Saturday as the
DCVZ breaks down.

&&

.FIRE WEATHER...
Issued at 1051 PM MDT Thu Apr 9 2026

Elevated to critical fire conditions will return to the plains,
higher valleys and foothills Sunday into Monday. Gusty southwest
winds will occur in some areas along with low humidity levels.

&&

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

&&

$$

DISCUSSION...RPK
AVIATION...20
FIRE WEATHER...RPK

NWS BOU Office Area Forecast Discussion