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Area forecast discussion 
National Weather Service Cheyenne Wyoming
432 am MDT Monday Aug 31 2015

Short term...(today through Wednesday night)
issued at 431 am MDT Monday Aug 31 2015

Scattered showers will continue early this morning ahead of a
shortwave moving up from the southwest within the right entrance
region of an upper level jet maximum. A few lightning strikes have been
observed over northwest Colorado the past few cant
rule out an isolated storm over the southern Wyoming mountains as
well. The cold front looks to be draped across northern Wyoming
according to 4am surface observation and should begin to move across our
eastern counties around sunrise. Ahead of the front...southwest
winds have become quite breezy overnight with gusts on average of
25 to 35 miles per hour...with a few spots along and west of the Laramie
range reporting higher speeds. Will see these winds persist
through the morning as the front slides south across the
plains...and winds behind the front will veer to the north
remaining gusty at times.

Temperatures will be cooler today in the Post frontal airmass with
readings expected to remain in the 70s and 80s. As the surface high
drops into the Central Plains...surface winds will veer further to a
southeasterly upslope component through the afternoon. Upper level
flow will remain out of the southwest with a continued stream of
subtropical maintained a chance for showers and
thunderstorms this afternoon over the mountains but also expanded slight
chances eastward within the upslope regime...although coverage in
this area will remain very isolated. Although low level moisture will be
higher than yesterday...gusty winds are still a good bet with this

Tuesday will be warmer as the colder airmass retreats to the east
and another shortwave embedded in southwest flow looks to move
overhead bringing additional chances for afternoon showers and
thunderstorms but mainly to the mountains. A strong upper low will dig
into the Pacific northwest on Wednesday and should deepen the leeside
pressure trough through Wednesday morning/afternoon. Surface winds will
increase in response with gusts of 30 to 35 miles per hour possible through the
afternoon out west as 700-500 mbs will ramp up to 25 to 35 kts. A
somewhat drier airmass will move in for Wednesday while temperatures
continue to warm under amplified southwest flow. Precipitation chances
will be less overall but cant rule out a thunderstorm or two over the

Long term...(thursday through sunday)
issued at 431 am MDT Monday Aug 31 2015

Thursday...dry and mild day under southwest flow aloft and with
limited low and middle level moisture to fuel thunderstorms.

Friday...flow aloft remains southwest. However...with an increase in
low and middle level moisture and low level upslope winds...expect
isolated late day showers and thunderstorms mainly along and east of
the Laramie range. more potent shortwave trough aloft moves across
Montana. Expect isolated late day thunderstorms to develop in our
counties along a convergence boundary.

Sunday...mostly dry day in the wake of a cold front as drier and
more stable airmass moves in.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 431 am MDT Monday Aug 31 2015

VFR prevails. Isolated to scattered afternoon and evening
thunderstorms from Cheyenne west with localized MVFR and gusty and
erratic wind.|


Fire weather...
issued at 431 am MDT Monday Aug 31 2015

Widely scattered light rain showers will continue to move northeast
across the district this morning. Breezy southwest winds of 25 to 35
miles per hour with a few higher gusts will also persist ahead of a cold front
that will drop south across the eastern plains after sunrise.
Winds across the plains behind the front will switch to the north
with gusts to 25 miles per hour...then will veer to the southeast through the
afternoon. A few showers and thunderstorms will return to the mountains and
nearby eastern plains this afternoon as energetic subtropical flow
remains overhead. Cooler temperatures today will be short-lived with very
warm...dry and breezy conditions looking to return to southeast
Wyoming through the end of the week.


Cys watches/warnings/advisories...


Short term...rjm
long term...Rubin
fire weather...rjm

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