FXUS65 KLKN 212125
Area Forecast Discussion
National Weather Service Elko NV
225 PM PDT SAT MAY 21 2016
.SYNOPSIS...It seems that low pressure has found a home over the
Great Basin. Unsettled weather in the form of showers and
thunderstorms, with some light snow at times, will last through
the middle of next week. Temperatures will remain below normal for
this time of year.
.SHORT TERM...Tonight through Tuesday. IR satellite imagery shows
an upper low pressure center circulating over southeast Oregon this
afternoon. There is still a predominant southwest flow aloft of
the Great Basin region however the pressure gradient has relaxed
and winds are not as strong as on Friday. Winnemucca had some
early morning rain showers and temperatures around the LKN CWFA
have risen into the 50s. More breaks of sun should lead to more
thunderstorm activity this afternoon. Radar imagery took on a
popcorn look late in the morning. The models are in pretty good
agreement for the short term period.
A general trough pattern will persist. The current low center
will move from southeast Oregon today and reposition over central
Canada north of the Dakotas. Another low will drop down into the
base of the trough in the meantime. Showers will occur daily with
afternoon and evening thunderstorms possible each day. This
persistent pattern will also keep bringing in cooler air. Snow
levels are likely to drop to near the valley floors periodically.
.LONG TERM...Tuesday night through Sunday. Long wave trough continues
over the western U.S. through the period, but ECMWF finally builds a
ridge along the coast late next week, while GFS continues the trough.
For now, the general consensus is that the trough will continue.
Tuesday night through Thursday both ECMWF and GFS move a closed
low eastward across southern Nevada into Utah. The low will keep
temps below normal although slowly moderating, along with a
continuing chance of showers and afternoon thunderstorms.
Thursday through Saturday the GFS takes a new upper low from the
Queen Charlottes southward along the coast, then eastward across
Oregon Sunday, close enough to affect northern Nevada. The ECMWF,
meanwhile, builds a strong ridge along the coast during that time.
On Sunday model differences become very large and forecast confidence
decreases. Model differences should resolve in the next couple days.
Snow fell as low as 5500 feet MSL Friday but the snow level will
gradually rise as the main upper trough and embedded lows slowly
.AVIATION...Generally VFR through Sunday with scattered to broken
cumulus. Scattered afternoon/evening showers and isolated
thunderstorms today, but fewer Sunday. Gusty west or northwest
winds decreasing around 04Z, then increasing again after 16Z