Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 150310

Area Forecast Discussion
National Weather Service Denver/Boulder CO
910 PM MDT Wed Mar 14 2018

Issued at 903 PM MDT Wed Mar 14 2018

Only minor adjustments planned for the grids at this time.
Broken to scattered cirrus overnight, increasing in coverage
on Thursday ahead of the approaching system. Timing from the
latest NAM12 still starting late aftn with the best chance of
showers Thursday evening.


.SHORT TERM...(This evening through Thursday)
Issued at 418 PM MDT Wed Mar 14 2018

High clouds will continue to spread over the area tonight. The low
levels west of the mountains will gradually moisten, perhaps
leading to some weak showers over the higher mountains late
tonight. Low levels east of the mountains remain dry.

On Thursday there will be quick cyclogenesis over eastern
Colorado, likely in the Limon area. There should be a surge of
easterly winds north of the low during the middle of the day,
though it`s unclear if this will progress all the way into Denver.
Meanwhile it will be dry, warm, and breezy on the south side of
the low. It`s likely that north winds will develop along the Front
Range briefly in the early afternoon. The main event will be a
convective blob along the trough axis that should move across the
mountains during the afternoon, through Denver mid to late
afternoon, and over the plains in the early evening. With a fairly
moist environment, some cooling aloft, and moderate forcing moving
in, plenty of showers should develop over the mountains. It will
be warm enough for a mix of rain and snow in the valleys. There
will probably be some heavy snow showers and a few thunderstorms over
the mountains, but they should also be transient, so snowfall
will vary but an inch or two should be common in the higher
mountains during the afternoon.

On the plains the dry air will remain over the south, with some
moisture moving in on the easterlies into the northeast corner.
This will set the stage for the evening activity out on the
plains. Convection moving off the mountains in the afternoon
should still be moving into a relatively dry airmass which should
limit the strength of any convection, but could promote gusty
winds. For this reason we will limit the PoPs, figuring the wind
will be more widespread. Temperatures should drop sharply in the
late afternoon around Denver, but still be warm enough that any
precipitation will be rain.

.LONG TERM...(Thursday night through Wednesday)
Issued at 440 PM MDT Wed Mar 14 2018

A trough and associated jet will move into the state Thursday
night. The placement of the jet to the south of the forecast area
will reduce the threat of high winds on Friday over the northern

The trough should bring snow to the high country late Thursday
night. Rain showers will spread onto the plains overnight.
Precipitation should continue through Friday with model QG showing
ample upward vertical motion across the plains. Early Friday
morning, temperatures should cool enough to allow rain to mix with
or change over to snow. Accumulations for the mountains are forecast
to be 3 to 6 inches, locally higher values will be possible. Little
to no accumulation over the plains.

Saturday night a less organized, weaker system is expected to
enter the forecast area. This should bring another chance of snow to
the mountains, with rain again spreading onto the plains. Rain
should change to snow on the plains Sunday morning as the system
progresses eastward.

Drier and warmer conditions return for Tuesday and Wednesday.


.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 903 PM MDT Wed Mar 14 2018

South/southeast winds 7-12 kt this evening will continue to
transition to south-southwesterly direction over the next couple
of hours. VFR through Thursday. Some uncertainty about wind
direction in the middle of the day as a low pressure center
develops nearby. Scattered showers and thunderstorms are expected
after 20z with localized gusts to 40 knots possible. Stronger winds
will then mainly be from the west to northwest at that time.

Issued at 418 PM MDT Wed Mar 14 2018

Warm dry conditions are expected over Lincoln and eastern Elbert
counties Thursday, with winds increasing by early afternoon. The
Fire Weather Watch will be upgraded to a Red Flag Warning for that
area. Elsewhere humidities will be higher, and winds will likely
be delayed until late afternoon behind the cold front.


Red Flag Warning from noon to 7 PM MDT Thursday for COZ246-247.



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