Area Forecast Discussion
Issued by NWS Cheyenne, WY

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789
FXUS65 KCYS 262332
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
535 PM MDT THU MAY 26 2016

.SHORT TERM...(This evening through Saturday night)
Issued at 247 PM MDT Thu May 26 2016

Longwave trough across the Intermountain West comprised of two low
pressure areas. Satellite pix show one of these low pressures
spinning into North Dakota, while the second one was beginning to
lift northeast into Colorado from the four corners area.
Showers/storms have been developing across northern Colorado and
southeast Wyoming since around noontime. Convective organization
has been pretty weak thus far. Latest HRRR shows convection
continuing to overspread the area through the rest of the
afternoon/evening with best severe thunderstorm threat associated
with discrete convective mode south and east of the CWA. That
said, there could be a few strong to marginally severe possible
across the southern Panhandle. Although weakening, this activity
will linger across the southern Panhandle well into the overnight
and even Friday morning as the upper-low slowly wobbles towards
the western high plains. May need to watch for pockets of fog
development Friday morning, but wasn`t confident enough to
include at this time.

The low pressure area moves very little, located near the CO/KS
stateline by Friday afternoon. Expect another round of more
isolated shower and thunderstorm chances Friday afternoon,
especially around the mountains. Temperatures will be cooler
Friday with highs only reaching into the 60s with perhaps a few
70s in the western Nebraska Panhandle. Cooler temperatures will
keep any severe weather threat at bay for Friday.

Upper-low accelerates east on Saturday, with zonal flow taking its
place across the CWA. Saturday will feature the first day of a
weak warming trend that will continue through Memorial Day.
Although there will be no significant systems passing through,
warm surface temperatures will yield enough instability for
another round of non-severe afternoon and evening thunderstorm
activity.

.LONG TERM...(Sunday through Thursday)
Issued at 247 PM MDT Thu May 26 2016

No big changes seen in the Sunday through Monday time period with
scattered mainly afternoon and evening showers and storms
continuing over much of the area as an upper shortwave approaches
from the west and weaker impulses eject northeast over the region
from an upper low over the desert sw. Somewhat drier and milder
weather looks to settle in over the CWA Tuesday and Wednesday as
the northern shortwave closes off an upper low near the NW
US/Canadian border and moves it slowly eastward through midweek.
Associated surface cool front passes across the CWA Tuesday night
bringing some cooler and drier air so expect less pcpn for Weds
and Thursday...more confined to the mtns. Surface high moves into
the central plains Weds night with return flow and warmer temps
for the CWA Thursday.

&&

.AVIATION...(For the 00Z TAFS through Friday morning)

VFR expected to prevail for all terminals this evening outside of
scattered showers and tstorms with brief periods of MVFR
visibilities possible. Low CIGS below 2500 feet AGL are possible at
KLAR...KCYS in southeast Wyoming...and also KSNY AND KAIA over
western Nebraska after midnight tonight and into early Friday
morning.

&&

.FIRE WEATHER...
Issued at 247 PM MDT Thu May 26 2016

No fire weather concerns through early next week. The current
weather pattern will remain in place with scattered showers and
thunderstorms expected nearly every day.

&&

.HYDROLOGY...
Issued at 247 PM MDT Thu May 26 2016

Will continue to keep an eye on the snow melt across Snowy and
Sierra Madre ranges in the weeks ahead but based on current forecast
temperatures this seasons snow melt is looking very steady. High
temperatures around 10000 feet will be in the 40s to lower 50s
through mid next week with lows mainly in the 20s to lower 30s which
should keep the slow and steady snow melt continuing. The snow melt
wild card is any heavy rain from thunderstorm activity but the
chances of that looks relatively low based on the forecast weather
pattern.

&&

.CYS Watches/Warnings/Advisories...
WY...None.
NE...None.

&&

$$

SHORT TERM...CAH
LONG TERM...RE
AVIATION...TJT/RE
FIRE WEATHER...CAH
HYDROLOGY...CAH



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