Area Forecast Discussion
Issued by NWS Cheyenne, WY

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FXUS65 KCYS 230533

Area Forecast Discussion
National Weather Service Cheyenne WY
1133 PM MDT SUN MAY 22 2016

.SHORT TERM...(Tonight through Tuesday)
Issued at 217 PM MDT Sun May 22 2016

A post-frontal air mass is in place across the area this afternoon
as a strong cold front moved east into central Nebraska during the
early morning hours. This should keep the resulting threat for svr
weather to our east, but still expect scattered to numerous shower
and thunderstorm activity with deep troughing aloft. Cool midlevel
air with H5 temperatures around -15 deg C is supporting MUCAPES in
the 250-500 J/kg range with weak cinh, and the latest radar trends
show increasing convection along the Laramie Range. Some potential
for small hail this evening, but it appears the overall threat for
severe weather is low.

A general unsettled weather pattern remains in place for Monday w/
large scale troughing in place. Convective coverage will not be as
high with modest moisture availability, but we still expect to see
a few showers/thunderstorms along the I-80 corridor as an 80kt H25
jetlet lifts across northern CO during the afternoon. Highs should
be similar to today with H7 temps around +3C to +6C. The 12Z model
suite brings a weak surface boundary across the high plains on Tue
afternoon along with a fast-moving midlevel shortwave. Modeled QPF
signals suggest enough support for convective initiation after 18z
so this may be our next chance for strong/severe storms. GFS CAPES
around 1000-2000 J/kg combined with strong 0-6km shear suggests at
least some potential for rotating updrafts. Low-level moisture may
be a bit meager though with dew points in the 40s, so do not think
widespread severe storms are likely attm.

.LONG TERM...(Tuesday night through Sunday)
Issued at 217 PM MDT Sun May 22 2016

Cool and unsettled weather expected in the long term as a trough
of low pressure remains over the PACNW through the upcoming week.
Will see daily chances for rain showers and thunderstorms. Best
chance for showers will be towards the end of the week as low
pressure tracks across Colorado.


.AVIATION...(For the 06Z TAFS through 06Z Monday night)
Issued at 1127 PM MDT Sun May 22 2016

latest radar loop was showing light showers exiting kaia with
clearing skies behind this batch of activity. wind speeds should
also continue to diminish through the night as high pressure
builds over the area. this will allow for vfr conditions to
prevail. a jet streak is progged to push through northern colorado
tomorrow afternoon and help induce a few showers and thunderstorms
along the co/wy mountain ranges. these showers and thunderstorms
may impact the lar/cys taf site in the afternoon. otherwise...vfr
conditions will be the rule.


Issued at 217 PM MDT Sun May 22 2016

No major fire weather concerns over the next several days with rhs
well outside of critical thresholds. Daily chances for showers and
thunderstorms will exist through the week.


Issued at 217 PM MDT Sun May 22 2016

Cooler temperatures behind a cold front that moved through
southeast wyoming last night has eased snow melt and the Upper
North Platte River at Saratoga and Sinclair has responded with
slower rises. Bump in the Laramie River at Laramie is a result of
snow melt yesterday and Thursday...expecting moderate flood stage
at Laramie Monday afternoon. Cooler temperatures expected through
much of the upcoming week which will keep snow melt on the low


.CYS Watches/Warnings/Advisories...


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