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Area forecast discussion 
National Weather Service Cheyenne Wyoming
issued by National Weather Service Rapid City South Dakota
250 PM MDT Thursday Oct 23 2014

Short term...(this evening through Friday night)
issued at 245 PM MDT Thursday Oct 23 2014

Dry and mild weather is expected through at least all of the
short term (tngt through Sat mrng). This will be in response to
slowly building heights and a dominant large-scale ridge across
the central Continental U.S.. the main items of interest will be gusty
southwest-west winds and relatively warm weather.

The latest water vapor images and rap model analyses indicated a
150-knots 300-mb jet crossing over the Pacific northwest with considerable
middle- and high-level clouds over much of the northwestern Continental U.S.. although a
thick patch of cirrus moved across the County Warning Area earlier today...the water
vapor trajectory suggests the bulk of the cirrus will remain northwest of
the County Warning Area...especially late tonight and Friday as the upper ridge builds.
Until then...expect some periodic dense cirrus patches as the jet
interacts with the mountains. BUFKIT time-sections for kcys support
this as well.

Gusty southwest-winds will occur especially near ridge tops tonight as
700-mb flow is 30-45 knots from the west with weak cold-advection that
will promote mixing. Looks to be just below High Wind Warning criteria
but it does bear watching. Although gusty winds will continue into
Friday they should be somewhat muted as 700-mb wind speeds decrease
by 5-10 knots and the upper ridge builds.

Given the upper ridge and 700-mb temperatures of 7-10c across the County Warning Area the
temperatures will be 15-20f above average through the short-term...and
approaching record levels on Friday. The relative humidity also will drop to near
15 percent across the southeastern Wyoming plains on Friday afternoon. Friday night will again
be quite mild for this time of year.

Long term...(friday night through thursday)
issued at 245 PM MDT Thursday Oct 23 2014

Unseasonably warm and dry weather will continue on Saturday as
ridge begins to shift east of the County Warning Area during the day. Highs will
be 10 to 20 degrees above average under mostly sunny skies.
Southwesterly winds will become breezy over western portions of
the County Warning Area during the day.

Clouds will increase later Saturday night and Sunday as the ridge
shifts further east...allowing a shortwave trough and surface cold
front to move across the region. The best chance for showers on
Sunday will generally be near and west of the Continental
Divide...with chances spreading over the rest of the County Warning Area Sunday
night into Monday. As colder air pushes in Sunday night...some
accumulating snow is possible Sunday night into Monday over at
least the south central Wyoming mountains.

Seasonable temperatures can be expected across the area through the
middle of next week...with a warmup possible again late in the week.
Mostly dry weather is anticipated Tuesday through Thursday.


Aviation...(for the 18z tafs through 18z Friday morning)
issued at 1126 am MDT Thursday Oct 23 2014

VFR conditions will continue this afternoon and tonight.
Considerable high cloudiness will persist this afternoon and into
tonight. Southwesterly winds will be gusty this afternoon over
much of southeast Wyoming...with gusts between 25 and 35 knots


Fire weather...
issued at 245 PM MDT Thursday Oct 23 2014

Continued warm and dry weather through Saturday with above normal
temperatures and gusty winds. Expect afternoon humidities to fall
into the middle to upper teens each afternoon. Fortunately...fuels
are reported as green for much of southeast Wyoming where the
strongest winds are expected to develop. So fire weather concerns
should be minimal. Temperatures will cool down considerably from
late Sunday into the middle of next week as low pressure slowly
tracks through The Rockies.


Cys watches/warnings/advisories...


Short term...bunkers/wfounr
long term...wfounr
fire weather...wfounr

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