National Weather Service Forecast Discussion

000
FXUS65 KBOU 040831
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
231 AM MDT Tue Oct 4 2022

.SHORT TERM...(Today and tonight)
Issued at 300 AM MDT Tue Oct 4 2022

Satellite shows the upper level low that brought several days of
unsettled weather is finally drifting slowly to the east into
western South Dakota. Lingering showers ahead of the trough axis
extending into eastern Colorado were moving east and will exit the
eastern plains early this morning. Meanwhile, a somewhat drier
and weakly subsident airmass will be spreading across the area
from the west. This will act to limit convective development
today, but still expect some shallow convection with lingering low
level moisture interacting with sufficient daytime heating. Most
of these will initially be confined to the high country this
afternoon, but by late in the day and especially this evening may
spread onto the adjacent plains and Palmer Divide area. Any
precipitation today will be light, but we did have to extend the
chance of showers drifting onto the plains this evening and even
overnight with an easterly upslope component in the wind fields up
to 9-10 thousand ft MSL. Temperatures will be near seasonal
averages again.

We`ll keep some patchy fog mentioned early this morning in the
high mountain valleys and South Platte River Valley north of
Denver this morning. Light winds, partial clearing, and narrow
T/Td spreads aiding formation. However, that will dissipate by
9-10 am with sufficient heating and mixing.

.LONG TERM...(Wednesday through Monday)
Issued at 207 AM MDT Tue Oct 4 2022

Drier air in northerly flow aloft will be over the area on Wed.
There still may be a chance of showers and isold storms over the
higher terrain along and south of I-70.  Across the plains it will
be dry.  Highs will be near seasonal levels.

On Thu, the flow aloft will become more northwesterly.  Cross-
sections show limited moisture so any shower activity will be rather
isolated over the higher terrain.  Highs will remain near seasonal
levels.

For Thu night into early Fri, a disturbance in NW flow aloft will
move across nern CO.  In addition, a cold front will move across the
area as well.  As a result will see a good chance of showers across
portions of the plains Thu night into early Fri. By Fri aftn,
there may be enough moisture over the higher terrain for a chance
of showers and a few storms. Across the plains, it will be dry
with cooler temps as highs may only reach the mid 50s to lower
60s.

Looking ahead to the weekend, the flow aloft will remain
northwesterly.  There could be some moisture embedded in the flow
which would affect mainly the mtns.  Thus will keep in a chc of
showers over the higher terrain with mainly dry conditions over the
plains.  Temperatures will remain near seasonal normals both days.

&&

.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 300 AM MDT Tue Oct 4 2022

The mid level cloud deck is breaking up, while the chance of a
lower MVFR stratus deck still appears to be quite low with lack of
any upslope. However, with the clearing we could see patchy
radiational fog develop. The main risk of this would be just to
the north of KDEN since light drainage winds should prevail most
of the night. However, a late night/early morning turn of winds to
the north or northwest could bring that fog threat into/near KDEN
11Z-15Z. There`s about a 20-30% chance that fog and visibility
under 1SM develops at KDEN.

Northeasterly diurnal winds are then expected to develop toward
15-17Z with any fog burning off into just a scattered stratus deck
at most. VFR conditions will prevail, but clouds will thicken
toward 00Z with a few showers also possible. Most of this cloud
deck should be above ILS approach limits, and closer to 7000-8000
feet AGL. That cloud deck could hold much of the upcoming night
with weak east/southeast flow.

&&

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

$$

SHORT TERM...Barjenbruch
LONG TERM...RPK
AVIATION...Barjenbruch

NWS BOU Office Area Forecast Discussion