Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 300010

Area Forecast Discussion
National Weather Service Cheyenne WY
610 PM MDT MON AUG 29 2016

.SHORT TERM...(This evening through Wednesday night)
Issued at 256 PM MDT Mon Aug 29 2016

Isolated convection noted over parts of the CWA this afternoon on
the northern fringe of an upper low currently over southwestern
Colorado. Shear is weak and expect individual cells to be rather
short lived...and dissipate entirely this evening as the low
levels cool and stabilize.

The upper low will weaken and open overnight while an upper ridge
builds northeast across Wyoming. This upper ridge then looks to
hold across Wyoming into Colorado Tuesday through Weds and should
cap off the atmosphere for the most part thus warm and generally
dry weather expected across the CWA. A bit of convection cannot be
ruled out around the mtns in the afternoons so will maintain some
very low pops there. Otherwise dry and warm overall both days. A
weak front may push up against the mtns Tuesday night as a surface
high slides down the northern plains but little cooling expected
from it. A little breezy over the plains on Wednesday in response
to a steepening gradient between the plains surface high and
falling pressures over the northern Rockys ahead of an approaching
upper trough.

.LONG TERM...(Thursday through Sunday night)
Issued at 256 PM MDT Mon Aug 29 2016

The upper level ridge will shift east of the CWA on Thursday
as a strong upper low over the Gulf of Alaska begins to push into
the PacNW. Sfc low pressure developing ahead of the upper low
over the northern plains/southern Canada through the end of the
week will strengthen the sfc pressure gradient across our CWA. In
response, fairly breezy south winds are expected over the plains
with southwest winds in the high country on Thursday. Conditions
look similar for winds on Friday, although stronger speeds are
expected out west as 700 mb flow increases here. Similar
conditions are likely for Saturday, and possibly on Sunday as
well if a cold front moving south across the central plains
cannot back its way westward. Current models are projecting the
front to stall across SD/NE, so kept breezy southwest winds in
the forecast, especially along and west of the Laramie Range.
Temperatures will remain warm through the period, although
cooling a bit by the weekend as the main upper trough begins to
move over the Rockies. Humidities look to hover in the teens and
20s through Saturday across southeast Wyoming. Therefore,
certainly could see fire weather concerns throughout the extended
period for these areas. Will see chances for showers/storms each
day as energetic southwest flow remains overhead. Can`t rule out
stronger storms from Friday through the weekend as the upper
trough approaches and winds aloft strengthen.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 610 PM MDT Mon Aug 29 2016

VFR conditions to prevail at area terminals thru the period.
Satellite images show broad area of mid/upper-level clouds
associated with a Colorado low pressure affecting KCYS and all of
the western Nebraska terminals. These will lessen as the evening
wears on, but still be present overnight. There have been a few
showers/weak thunderstorms that have managed to develop, but
coverage is so isolated felt comfortable enough to exclude from
the TAF`s at this time. Even less convective coverage and cloud
cover anticipated for Tuesday afternoon.


Issued at 256 PM MDT Mon Aug 29 2016

Fire weather concerns expected to remain low through Wednesday
with weather factors non-critical. Concerns higher late in the
week as winds should increase at that time.


.CYS Watches/Warnings/Advisories...



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