Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 242012

Area Forecast Discussion
National Weather Service Denver/Boulder CO
212 PM MDT Sat Mar 24 2018

.SHORT TERM...(This evening through Sunday)
Issued at 212 PM MDT Sat Mar 24 2018

Southwest flow aloft will prevail tonight and Sunday ahead of an
upper level trough over the Pacific Northwest and Great Basin.
High clouds over Colorado extend southwest across the Desert
Southwest. They will continue to stream over the region through
tonight and into Sunday. Some models are showing precipitation
over the mountains this afternoon and evening. This is due to a
few convective showers. So far cumulus clouds are having a hard
time forming. Will keep the mention of showers out of the forecast
for tonight except for far north central Colorado.

A surface low will deepen over southeast Colorado Sunday. This
will bring increasing east to southeast winds to the eastern
plains. This will increase low level moisture through the day. A
few showers and thunderstorms may form late in the afternoon as
the airmass becomes unstable. Better chance for precipitation
looks to be in the evening hours. Highs Sunday will mild and in
the 60s for most of northeast Colorado. The far northeast corner
may stay under low clouds for most of the day and stay in the 50s.

.LONG TERM...(Sunday night through Saturday)
Issued at 212 PM MDT Sat Mar 24 2018

Sunday night, weak mid level qg ascent will be over the cwa ahead
of the upper trough axis along the eastern ID/western WY line by
06z Monday, it then lifts north and east of the region by 12z
Monday. At the sfc, an area of low pressure will be over southeast
CO with an inverted trough extending northward. This will result
in a weak east/northeasterly surge coupled with weak forcing
aloft that could produce isolated to scattered showers Monday
evening, following by areas of stratus and lingering drizzle
overnight. The best chance of showers will be along the northern
border. Monday and Monday night, weak mid level qg ascent will
increase from the southwest, ahead of the southern branch of the
trough located in the Great Basin region 00z Tuesday. In addition,
a cold front will push into the cwa from the north/northeast
upslope from the surface to around 700 mb through Monday evening
then weakening overnight. The qg ascent associated with the trough
shifts south overnight with the trough, which will allow the pcpn
over the cwa to taper off as well. Greatest qpf occur in the
evening period, then lighter qpf lingering over the southern part
of the cwa late Monday night and Tuesday morning. At this time,
models generating advisory type snowfall in zones 34, 36 and 41
with potential amounts in the 4-10 inch range there. Tuesday and
Tuesday night, there will be a weak deformation zone over the
region through midday, then a cool and drier northwesterly flow
kicks as the trough exits east and mid level subsidence/qg
descent occurs Tuesday afternoon and Tuesday night. The next
transition will occur late Wednesday and Wednesday night. An upper
trough is progged to drop out of the northern Rockies with
increasing qg ascent from north to south around 00z Thu. A cold
front, following by upslope and weak mid level qg ascent is still
progged for Wednesday night. Enhanced bands of pcpn, mainly snow,
could also be part of the equation at that time with a passage of
an upper level jet. This system still appears to exit the region
by midday Thu, allowing for a dry northwesterly flow to occur late
Thursday into the weekend.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 212 PM MDT Sat Mar 24 2018

Winds will remain a south to southeast direction through tonight.
Wind gusts to 30 knots will be possible through mid evening, 03Z.
Low clouds will enter eastern Colorado tonight with ceilings under
1000 feet. At this time, appears these low clouds will stay east of
the Denver area. However, there is a small chance they reach KDEN
for a short time.




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