Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 140259 AAA

Area Forecast Discussion...UPDATED
National Weather Service Cheyenne WY
859 PM MDT Thu Oct 13 2016

Issued at 859 PM MDT Thu Oct 13 2016

Upgraded Fire Weather Watch to a Red Flag Warning earlier for
areas along and east of the Laramie Range. Minor adjustments to
winds for the rest of tonight. Still expecting winds to pick back
up across the higher elevations of Carbon and Albany counties
toward morning. We may need high wind headlines tomorrow for parts
of Carbon and Albany counties as we may be gusting close to High
Wind Warning criteria by the afternoon. will let midnight shift
take a closer look at that. Otherwise...tomorrow promises to be
dry and rather breezy to downright windy for parts of the area.


.SHORT TERM...(This evening through Saturday)
Issued at 320 PM MDT Thu Oct 13 2016

The Red Flag Warning is in good shape for today as many locations
within the warned area are experiencing critical fire weather
conditions this afternoon. Winds and humidities will ease with
sunset, but will remain fairly gusty in the wind prone areas along
and west of the Laramie Range overnight. 700 mb winds will average
in the 40 kt range over these areas, and a weak shortwave trough
moving across the forecast area overnight will likely force gusts
of 45 to 55 mph down to the surface in the gap winds near
Arlington area and perhaps even near Bordeaux as well.

The strong upper level system plowing into the Pacific Northwest
today and Friday will maintain windy conditions through Saturday.
Strong southwest winds are possible on Friday across Carbon
County as 700 mb winds will once again average in the 40 kt range
over this area with deep mixing up above this level. Gradient
progs remain under 50 meters though so still thinking gusts at the
surface will be 50 to 55 mph, which is under high wind criteria,
so will hold off on highlights for now. The Fire Weather Watch
looks to be in good shape for tomorrow with the dry downslope
westerlies expected. Will let the evening shift upgrade the watch
once today`s Red Flag Warning expires. Not much in terms of
moisture is anticipated the next couple of days as the best fetch
stays to our north and west. Cannot rule out a few rain/snow
showers over the higher mountains Friday night thru Saturday
morning but chances look less than 50 percent.

.LONG TERM...(Saturday night through Thursday)
Issued at 320 PM MDT Thu Oct 13 2016

The main concern with this portion of the forecast is how potent
the jet energy will be as it moves through the Northern Rockies
late this weekend into early next week.

Saturday night-Sunday:
The models are showing our initial surge of jet energy moving
towards southern Wyoming late Saturday night and lifting northeast
towards the northern plains by Sunday evening. The position of
this jet will keep most of the synoptic scale lift and best
precipitation chances in northern Wyoming. However, our gap areas
will start feeling the stronger winds beginning late Saturday
night and continuing through Sunday. Would not be surprised if
wind highlights will be issued for those gap areas during that

Sunday night-Monday:
This jet energy will begin to dive south on Sunday night and
Monday as an upper level trof skirts along Northern Montana
towards the northern Plains. The shortwave energy will cause a
pacific frontal boundary to surge through the area on Monday with
the potential for a bora wind event. These bora winds could
impact the entire area Monday and Monday evening. The NAEFS/GEFS
ensembles are in very good agreement with this picture with wind
speeds around 2 to 3 standard deviations above normal for this
time of year. We will continue to see how things evolve during
the next couple of days, and bump up wind speeds from the blends.

Monday night-Thursday:
Cool air will remain entrenched over the area through Wednesday,
but wind speeds should begin to lighten up. Meanwhile, warmer
temperatures will be in store for the remainder of the weekend as
an upper level ridge builds over the Rockies.

.AVIATION...(For the 18Z TAFS through 18Z Friday afternoon)
Issued at 1127 AM MDT Thu Oct 13 2016

Benign weather conditions are anticipated during the next 24 hrs.
However, it will become quite breezy mainly in areas west of the
Laramie Range including RWL where they may have gusts of 35 to 40
kts Friday morning. VFR conditions will be the rule as the lee
side trof remains in place with limited moisture.


.AVIATION...(For the 00Z TAFS through 00Z Friday evening)
Issued at 520 PM MDT Thu Oct 13 2016

High level cloudcover will spread in across SE Wyoming and the
western Nebraska Panhandle tonight ahead of an approaching upper
level disturbance. We are not expected anything below VFR
category on ceilings for the next 24 hours. Winds will decouple
after sunset this evening and drop below 10 knots at all
airports, but we are expecting winds to increase again by late
tomorrow morning from the southwest with gusts 30 to 40 kts at
Rawlins, Laramie and Cheyenne by early afternoon with gusts around
25 kts across the western Nebraska Panhandle tomorrow.


Issued at 859 PM MDT Thu Oct 13 2016

Updated earlier this evening to upgrade the Fire Weather Watch to
a Red Flag Warning for Friday for areas along and east of the
Laramie Range. Rest of fire weather forecast still on track for
wind and low RH tomorrow.  JG

Previous Fire Weather Discussion issued at 320 PM MDT THU Oct 13

Dry and windy conditions will persist over much of southeast
Wyoming this afternoon. The Red Flag Warning currently out for
FWZ 301 and 308-310 is in good shape, with multiple sites
reporting critical conditions across the warned area. Elevated
fire weather conditions have also developed further west across
lower elevations of Carbon County, but these should only last
another hour or two as winds will ease and humidities will rise
with sunset. Windy conditions will continue mainly in the wind
prone areas along and west of the Laramie Range tonight, with a
more widespread threat for critical fire weather conditions
expected tomorrow as stronger winds and continued dry humidities
are forecast. Windy conditions look to continue through early next
week with little precipitation expected. RJM


WY...Red Flag Warning from 11 AM to 6 PM MDT Friday for WYZ301-302-

NE...Red Flag Warning from 11 AM to 6 PM MDT Friday for NEZ311>313.



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