Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 240018

Area Forecast Discussion
National Weather Service Denver/Boulder CO
618 PM MDT Fri Mar 23 2018

Issued at 615 PM MDT Fri Mar 23 2018

Have extended the showers/thunderstorm coverage over the plains
further into this evening with still shower activity over Western
Colorado. Still some rather stronger looking storms over Morgan
county which could result in near severe limits with strong winds
and some small hail.

Have allowed the winter weather advisory to expire for the
mountains but still a few more bands of showers to move though.
Overall, any additional accumulations will be 2 inches or less
with rapidly changing weather conditions in the showers.


.SHORT TERM...(This evening through Saturday)
Issued at 218 PM MDT Fri Mar 23 2018

An upper level trough over Colorado and the left exit region of
the jet will continue to bring scattered showers, isolated
thunderstorms and windy periods through early evening. A quick 1-3
inches of snow remains possible for the mountains which will
likely produce slippery roads. Therefore, will keep the Winter
Weather Advisory in effect for the mountains until 6PM. Downslope
winds will likely prevent convection from forming in the foothills
and across the Front Range. For the northeast plains, models show
additional showers and storms forming later this afternoon and
into the early evening. Will keep isolated/scattered pops in the
forecast for here until early evening. Eventually subsidence and
drying will move in behind the trough late this evening bringing
mostly clear skies. There is a slight chance for low clouds over
the far northeast corner of the state where enough low level
moisture may creep into the state.

A weak ridge moving across the state will result in mostly clear
skies Saturday morning. High temperatures will again be mild with
readings in the mid 60s to lower 70s. An upper level trough
digging south over the Pacific Northwest will increase Pacific
moisture resulting in high clouds moving in late in the day.

.LONG TERM...(Saturday night through Friday)
Issued at 218 PM MDT Fri Mar 23 2018

Saturday night through Sunday, a generally dry southwesterly flow
aloft will be over the region. On Sunday, a surface low will be
over southeast CO with an inverted sfc trough extending northward
into the Urban Corridor. This would appear to induce an Denver
Cyclone with cooler air and better low level moisture north of
Denver. High temperatures would not be as warm as forecast if this
scenario play out. Dry south/southeasterly sfc winds will allow
for elevated fire danger to persist, primarily over southern
sections of Elbert and Lincoln counties. Showers are progged to
develop Sunday evening, primarily the result of low level upslope.
The GFS is a little further north with these features, with the
main focus from around fort collins northward Sunday evening.
Overall, isolated to scattered pops overall for Sunday night with
the best coverage along the northern border.

The next system is expected to impact the region late Monday and
Monday night.  The models have a strong southwesterly flow aloft
over CO 00Z Monday ahead of the upper level trough sitting over
south central ID.  Some of the energy from the trough is progged
to lift east/northeast western WY by 12z Monday,  and into the
northern Great Plains by 00z Tue, while the southern part of the
trough drops into the Great Basin.  A cold front associated with the
northern branch pushes southward into the cwa late Monday afternoon,
with shallow upslope developing in the evening.  Best chance of
precipitation would appear to be over the Palmer Divide and
southern Front Range Foothills.  Weak to moderate mid level qg
ascent will be stretch across southern and eastern CO Monday night,
decreasing and shifting southward by 18z Tuesday.   A drier and more
stable northwesterly flow Tuesday afternoon and Tuesday night.  A
weak upper level ridge will be over the region on Wednesday under a
northwesterly flow aloft.  The next system is progged to drop out of
the northern Rockies and into northeast CO Wednesday afternoon into
Thursday morning.  Colder temperatures with this system should add
up to another chance of snow over the higher terrain with snow or a
mix of rain and snow over the northeast plains.  Late Thursday into
Friday, increasing stability with a drier northwesterly flow aloft
over the region.


.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
Issued at 218 PM MDT Fri Mar 23 2018

There is still a slight chance for a shower or thunderstorm
through 02Z. Do expect another windy period and after 21Z with
west winds gusting to 35 knots. A cool front moves across and
winds shift to the northeast around 02-03Z. Winds will gradually
shift to a southerly drainage direction by 09z. On Saturday winds
become south- southeast with gusts to 25 knots.


Issued at 218 PM MDT Fri Mar 23 2018

The fire danger will remain elevated Sunday afternoon, primarily
over the Palmer Divide. No highlights at this time, but will need
to continue to keep a close eye on southern portions of Elbert
and Lincoln counties.


Red Flag Warning until 7 PM MDT this evening for COZ247.



LONG TERM...Cooper
FIRE WEATHER...Cooper is the U.S. government's official web portal to all federal, state and local government web resources and services.