Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 180355
AFDBOU

Area Forecast Discussion
National Weather Service Denver/Boulder CO
955 PM MDT Tue Apr 17 2018

.UPDATE...
Issued at 955 PM MDT Tue Apr 17 2018

Last of the High Wind Warnings on the eastern plains have been
allowed to expire as winds slowly diminish. Forecast for a cool
night and lighter winds on track.

&&

.SHORT TERM...(This evening through Wednesday)
Issued at 756 PM MDT Tue Apr 17 2018

Last surge of high winds had spread across the plains and just
brushing up against the Denver area. Main punch of this push will
move through Lincoln county over the next hour. Winds are already
subsiding behind this so the High Wind Warning on the plains
expiring at 9 PM looks fine.

Overall minor adjustments for the latest wind trends, and snow
trends in the mountains where snow showers slow to decrease.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 218 PM MDT Tue Apr 17 2018

For Wednesday night into Thursday increased subsidence with the
incoming upper level ridge will continue the warm and dry pattern
across the state. Temperatures will be slightly warmer than
Wednesday with 700 mb values +5 degrees C warmer bringing highs in
the upper 60s. The main story of the long term continues to be the
storm moving onshore by California Thursday morning that is
currently forecasted to impact Colorado by late Thursday through
Friday. Southwest flow ahead of the upper closed low will increase
by Thursday afternoon. A deepening surface low pressure system over
eastern Utah will help to increase the pressure gradient over the
eastern plains and pull mid-level moisture up from the plains. This
will help to bring some gusty winds by the late afternoon and
evening to the plains as well as increasing clouds ahead of the main
system.

By Friday morning both the EC and the GFS have the 551 DM closed low
over Utah with increasing lift associated with the approaching jet
moving into southern CO. Precipitation is forecasted to start over
the mountains by the morning hours on Friday with the potential for
some thunderstorms by the afternoon over the higher terrain. Out on
the plans precipitation will most likely start out as rain with
coverage over most of the NE plains and Front Range. There is a cold
front expected to bring in increased NE winds and colder
temperatures in the mid levels by Friday night. Current model
soundings indicate a column cold enough for snow with decent QG lift.
With the NE flow and cooler air pooling against the foothills cold
air damming could bring decent snowfall amounts to the foothills by
early Saturday. QPF values still vary between models but numbers are
progressively higher along the foothills and Monument hill areas
where upslope is expected to be the best. However, most areas will
see precipitation accumulation by Saturday afternoon. Models
indicate a stacked low over SE Colorado by Saturday morning that
will slow the systems progression and push precipitation into the
late afternoon hours on Saturday. Temperatures will drop slightly
with below freezing in the mountains and 40s to 50s on the plains
with freezing overnight. As dry air intrudes to the south of the
closed low it will push the system into the TX Panhandle by Saturday
evening. Wrap around from the low will continue to bring some
rain/snow to the NE plains before gradual clearing overnight into
Sunday.

For Sunday into Monday upper ridging and subsidence will return with
a warming trend. At this time temperatures are looking to once again
scratch the 70 degree mark by Monday.

&&

.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 955 PM MDT Tue Apr 17 2018

Northwest winds will still be gusty, and one last surge of gusts
to around 40 knots from the north/northwest expected at KDEN
til around 03-04Z before winds finally weaken and gradually turn
more westerly overnight. Northerly winds may increase again by
15Z-18Z Wednesday before decreasing and turning more easterly by
21Z.

&&

.FIRE WEATHER...
Issued at 955 PM MDT Tue Apr 17 2018

The last of the Red Flag Warnings have been allowed to expire as
humidities continue to increase, and winds slowly subside. There`s
still some wind combined with low humidity over the eastern plains
Wednesday, but values should not reach Red Flag criteria.

&&

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

&&

$$

UPDATE...Barjenbruch
SHORT TERM...Meier
LONG TERM...Bowen
AVIATION...Barjenbruch
FIRE WEATHER...Barjenbruch



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