Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 290322 AAA

Area Forecast Discussion...UPDATED
National Weather Service Cheyenne WY
922 PM MDT SAT MAY 28 2016

Issued at 914 PM MDT Sat May 28 2016

Recent radar trends indicated an overall decrease in coverage and
intensity of convection this evening.


.SHORT TERM...(This evening through Monday Night)
Issued at 249 PM MDT Sat May 28 2016

Some showers and storms moving east across mainly the northern
parts of the CWA this afternoon but low shear and modest
instability keeping them fairly benign. Expect this activity to
diminish this evening as the boundary layer cools and instability
falls off.

No major changes in the overall weather pattern seen across the
area through Monday with a weak upper low over moving slowly east
over the desert SW and a stronger upper low that should move to
the Montana/southern Canadian border on Monday. Weak impulses
will move across the CWA in a generally westerly upper flow and
combine with instability to produce scattered mainly afternoon and
evening convection. Somewhat better shear and instability expected
across the northern parts of the CWA Monday as the upper low moves
a little closer so some stronger storms a better bet on that day
in that area. Otherwise temperatures seasonal over the next couple

.LONG TERM...(Tuesday through Friday Night)
Issued at 249 PM MDT Sat May 28 2016

Models remain in agreement with swinging an upper level trough
across the high plains on Tuesday and Tuesday night, while surface
high pressure builds in from the west. The attendant cold front
is expected to be through our forecast area to the south by
Tuesday morning, so forcing for any ascent will be focused along
the Laramie Range and higher mountain peaks in upslope flow, and
where best instability will occur with cooler air aloft. High
pressure at the surface and a building ridge overhead will limit
convection for Wednesday although there remains a low chance for a
weak shower/storm over the higher peaks. Similar conditions will
persist for Thursday and Friday, while temps warm with the upper
ridge moving overhead. Could begin to see an increase in snowmelt
at this time, thus will have to monitor rivers closely for
potential rises.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 527 PM MDT Sat May 28 2016

VFR prevails. Isolated thunderstorms through 02Z producing
localized MVFR and gusty and erratic winds. Areas of IFR from 09Z
to 14Z in fog and low clouds at Chadron, Alliance and Scottsbluff.
Isolated thunderstorms again Sunday afternoon.


Issued at 249 PM MDT Sat May 28 2016

Fire weather concerns to remain low into the early part of next
week with non-critical conditions continuing. There will be
widely scattered mainly afternoon and evening showers and
thunderstorms into early next week with wetting rains from some of


Issued at 249 PM MDT Sat May 28 2016

The North Platte and Laramie Rivers will continue to run high,
but should remain steady or slowly recede over the next couple of
days with relatively steady reservoir releases and reduced
snowmelt from cool mountain temperatures. Warmer temperatures
next week will begin to increase snow melt again, so rivers will
be on the rise.


.CYS Watches/Warnings/Advisories...


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