Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 102217

Area Forecast Discussion
National Weather Service Denver/Boulder CO
317 PM MST Sun Dec 10 2017

.SHORT TERM...(This evening through Monday)
Issued at 317 PM MST Sun Dec 10 2017

Mostly clear skies and a dry atmosphere will lead to redevelopment
of strong inversions in low lying areas again tonight. Have
refined the low temps to adjust favored valley locations colder
tonight.  Meanwhile, it will remain quite mild along the Front
Range with light drainage winds.

For Monday, a cold front will bring slight cooling to the plains,
with temperatures a few degrees cooler than those observed today.
However, winds will increase over the northern border and eastern
plains with high fire danger...see Fire Weather section below.

.LONG TERM...(Monday night through Sunday)
Issued at 317 PM MST Sun Dec 10 2017

Models continue to show a mild and dry week ahead for Colorado.
The strong western U.S. ridge is forecast to hold its position to
the west of us all week long. By the end of the week the ridge
axis will retrograde from a position over Nevada and Idaho to a
position over the West Coast. This will bring Colorado under
stronger northwesterly flow from Wednesday night through Thursday.
The ECMWF shows an initial surge of moisture making its way over
the ridge and into Colorado by Thursday morning, but the GFS is
much drier. Will favor the dry GFS solution which doesn`t bring
precipitation to Colorado until next Saturday, when the upper
ridge is forecast to give way to a more significant trough that
comes ashore over the Pacific Northwest. The ECMWF also shows the
passage of a trough next weekend, so the forecast will favor that
solution and mention the chance of snow in the mountains next
Saturday. Until then, surface pressure gradients will be weak
after Monday afternoon, and flow aloft will also be weak under the
anomolously high heights that will dominate the weather pattern.
Temperatures on the plains will be about 10 to 15 degrees warmer
than normal through the week. Conditions in the mountains will
also be mild for December, but not as warm as on the plains.
Mostly clear skies during the overnight hours will allow
temperatures to drop to around seasonal values.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 317 PM MST Sun Dec 10 2017

VFR conditions will persist through Monday, with only a few high
clouds. Light/variable winds will transition back to south/
southwest 7-14 knots after 01Z. On Monday, winds may maintain a
southeasterly component through the day with anticyclone
development more likely.


Issued at 317 PM MST Sun Dec 10 2017

Winds will increase across the eastern/northern plains behind a
frontal push early Monday morning. Strongest winds with gusts to
30-40 mph will occur along the Wyoming border and over the eastern
plains where gradient and winds aloft are strongest. Humidities
bump up just a bit tomorrow with slight cooling and moistening.
However, the stronger winds will be sufficient to produce critical
grassland fire danger so issued a Red Flag Warning for locations
with the strongest winds.


Red Flag Warning from 11 AM to 5 PM MST Monday for COZ238-242-



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