Area Forecast Discussion Issued by NWS Denver/Boulder, CO
000
FXUS65 KBOU 160017
AFDBOU
Area Forecast Discussion
National Weather Service Denver/Boulder CO
617 PM MDT Mon Apr 15 2024
.KEY MESSAGES...
- Critical fire weather conditions over the plains through early
evening.
- Heavy mountain snow expected tonight and Tuesday morning.
- Strong winds to 65 mph over the eastern plains Tuesday.
- Cooler, breezy and unsettled through Saturday with precipitation
off and on. The best chances will be Wednesday night into
Thursday morning and again Friday afternoon into Saturday.
- Drier and somewhat warmer for Sunday and Monday.
&&
.SHORT TERM /Through Tuesday/...
Issued at 220 PM MDT Mon Apr 15 2024
Water vapor satellite imagery showing an upper level low moving
into western Colorado. Deep mixing under the strong southerly flow
ahead of the low is bringing southwest winds to 50 mph across the
eastern plains. Surface low pressure over northeast Colorado will
continue to deep as it slowly tracks northeast. A cold front will
cause winds to shift to the west this evening. Winds are expected
to remain gusty with gusts to 50 mph. Areas in and near the
foothills could see gusts to 60 mph. These downslope winds should
limit precipitation chances this evening. Expect winds to shift
northwest to north overnight. The best chance for showers will
come during this period when the downslope component will be
weakest. Expect an area of showers to form on the backside of the
low late tonight and Tuesday morning over the plains.
For the mountains, snow becomes widespread this evening and
continues overnight and into Tuesday morning. Drier moves into
the area late Tuesday morning and is expected to bring the rain
and snow to an end by early Tuesday afternoon.
Tightening pressure gradient and deep mixing may bring high winds
to the eastern plains Tuesday with gusts to 65 mph possible. Main
window for the strong winds will be late morning and afternoon.
As the airmass stabilizes, winds will decrease early Tuesday
evening. Upgrade the High Wind Watch to a Warning.
&&
.LONG TERM /Tuesday night through Monday/...
Issued at 220 PM MDT Mon Apr 15 2024
Brief weak upper ridging with weak northwesterly flow aloft can
be expected Tuesday night with no precipitation. A slowing moving
upper level trough/closed low over the northern U.S, and southern
Canada will push slowly eastward the entire week. Colorado will
be at at the bottom of the broad trough Wednesday into Friday,
with a zonal jet maximum to our immediate north and 70-100 knot
westerly flow aloft over our CWA. A decent cold front is expected
to move into the area late Wednesday afternoon/early evening.
There is upslope progged behind the front through Thursday on into
Friday morning. There is decent enough moisture progged to keep
pops going into Friday morning with the best coverage of 40%-80%s
Wednesday night into Thursday afternoon. There is minor CAPE
progged, mainly over the mountains late day Wednesday and again
late day Thursday. Will leave the "slight chance" of thunder in
then. It looks like there shouldn`t be much snow over the plains
and only modest amounts in the mountains. Precipitation amounts
go not look significant, but, hopefully, most areas will get
something.
Looking at temperatures, the warm day will be Wednesday, with highs
over the plains around 70 F. Thursday`s highs cool off about 20
degrees F.
For the later days, Friday through Monday, models show a weak upper
trough for later Friday into Saturday morning to bring increased
moisture and a better chance of precipitation for the forecast area.
There is flat upper ridging to move in late Saturday into Sunday. By
Sunday night and Monday, model solutions diverge somewhat, however
all of them point to a drier Sunday and Monday with a minor
temperature increase.
&&
.AVIATION /00Z TAFS through 00Z Tuesday/...
Issued at 615 PM MDT Mon Apr 15 2024
A cold front/outflow boundary has raced through DEN and will move
through APA by 01Z. Winds may briefly gust in excess of 40 knots
at all terminals. Winds will continue to be gusty out of the west-
northwest throughout most of the evening before decreasing in the
late evening hours. Most of the time tonight, the terminals will
have wind speeds less than 20 knots.
There is a chance that, during the later overnight hours tonight,
showers could form over the terminals. These could reduce
visibility slightly to around 3 miles and ceilings to around 3
kft. It is more likely that around or shortly after 12Z, a larger
band of precipitation moves across the terminals. This band of
precipitation could reduce visibility and ceilings much lower,
down to 0.5 SM or 1,000 feet, respectively. However, the majority
of the time, visibility and ceilings will only be reduced to
around 6 SM and 3 kft. During the late morning to around midday,
strong northwest winds will develop and will clear out the
precipitation and ceilings.
&&
.FIRE WEATHER...
Issued at 220 PM MDT Mon Apr 15 2024
Windy and very dry conditions will continue through early evening
over eastern Colorado. Relative humidities have fallen into the
single digits over the plains with wind gusts 40 to 50 mph. A cold
front will bring a wind shift early this evening. Winds will
remain gusty behind the front with gusts to 40 mph. Relative
humidities will improve behind the front with a chance for rain
showers, mainly late tonight and Tuesday morning.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 3 PM MDT Tuesday for COZ031.
Winter Storm Warning until 3 PM MDT Tuesday for COZ033-034.
High Wind Warning from 6 AM to 6 PM MDT Tuesday for COZ038-042-
044-046>051.
Red Flag Warning until 8 PM MDT this evening for COZ241-244>251.
&&
$$
SHORT TERM.....Meier
LONG TERM......RJK
AVIATION...Danielson
FIRE WEATHER...Meier