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Area forecast discussion 
National Weather Service Cheyenne Wyoming
534 PM MDT Friday Aug 28 2015

Short term...(this evening through Sunday night)
issued at 315 PM MDT Friday Aug 28 2015

Pretty quiet weather this afternoon as the upper level
trough...which brought some rain to the area last night and
Thursday...continues to move eastward across the Great Plains and
into the Great Lakes region through tonight. Subsidence behind the
trough has resulted in decreased convection due to warmer air
aloft. Still can not rule out an isolated thunderstorm over the
mountains and adjacent High Plains and valley locations. Kept pop
around 15 percent for Laramie and Cheyenne into this evening.
Added smoke to the forecast over the northern zones from Lusk to
Chadron as visibilities have been less than 6 miles this

Upper level ridge axis currently west of the forecast area will
drift eastward over southeast Wyoming and eastern Colorado on
Saturday. High temperatures will respond with readings in the middle
80s to middle 90s across the area...warmest over the lower elevations
of western Nebraska. It will be dry on Saturday so kept pop below
5 percent.

For Sunday...models indicate the ridge axis translating eastward
into the Great Plains with southwest flow increasing over the
forecast area. Some subtropical moisture will begin to move
northward over Colorado and Wyoming. Sunday will likely be the
warmest day of the week with highs in the middle 80s over the high
valleys including Laramie...and in the 90s over the High Plains.
Thunderstorms will return to the area so increased pop over mainly
southeast Wyoming for widely scattered coverage. Isolated thunderstorms
are possible east of i25 towards western Nebraska.

Long term...(monday through friday)
issued at 300 PM MDT Friday Aug 28 2015

A generally west-southwest flow aloft will hold across the County Warning Area for much of
the week...becoming more southwesterly Thursday and Friday as an upper trough
lifts across the northwest Continental U.S.. this will provided mainly dry and warm
weather to the County Warning Area for the week though isolated convection
possible over the mountains at times with any weak impulse riding
northeast across the region. Most widespread convection looks
like it will be Monday afternoon with one impulse moving by then
drier air should arrive for the Tuesday through Thursday time
period. On Friday some increase in moisture may occur as the
upper trough lifts into the northern rockies thus isolated activity
may return at that time.


Aviation...(for the 00z tafs through 00z Saturday evening)
issued at 531 PM MDT Friday Aug 28 2015

No aviation concerns tonight or tomorrow. Winds will be light
through tonight. Some smoke from wild fires in the northwest Continental U.S.
Will settle over the forecast area but still looking at VFR with
visibilities mainly 5 miles or greater. No chances for
thunderstorms tonight or Saturday. Winds may gust upwards of 25
miles per hour Saturday afternoon.


Fire weather...
issued at 204 PM MDT Friday Aug 28 2015

Fire weather conditions are expected to become elevated on
Saturday due to lower relative humidities. However...will not
issue a Fire Weather Watch at this time due to low confidence in
persistent gusty winds. Even across the western zones...model
soundings show winds decreasing aloft as mixing occurs during the
afternoon. This is due to an upper level ridge axis pushing across
the area on Saturday. Will word western and northern zones for
elevated conditions and will keep an eye on wind forecasts over
the next 24 hours since red flag conditions can not be ruled out.

Fire weather concerns will decrease by early next week as
subtropical moisture begins to push northward from the eastern


Cys watches/warnings/advisories...


Short term...tjt
fire weather...tjt

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