Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Elko Nevada
251 am PST Thursday Dec 25 2014
Synopsis...a low pressure system will continue to bring snow and
blowing snow to eastern Nevada today. As winds subside tonight...an
extended cold weather pattern will set in.
Short term...today through Saturday. The models are still in
very good agreement for the short term period.A cold trough axis
is centered through Elko this morning. A line of precipitation
formed west of Elko around midnight on the backside of the trough
axis that is stretching back towards Eureka in a slight positive
tilt fashion. There will be a couple more vorticity features to move
south across eastern Nevada today in transit to the base of the
trough. These features will incite more showers. However showers
across areas to the west of Elko are beginning to wane this
morning...so the Winter Weather Advisory for Humboldt County has
been dismissed. As of 2 am PDT...Road conditions were still very
hazardous...even in Humboldt County...with chains and snow tires
required. Chains and snow tires are also required for portions of
Interstate 80...Highway 93...LaMoille Highway...Mountain City
Highway and sections of Highway 50. Winds are still gusting over
40 kts at Tonopah and are beginning to increase at Wendover as
wind direction is currently shifting northeast.
Christmas day. As a cold front slides south with the trough
axis...snow and blowing snow will continue to be a travel hazard
across eastern Nevada due to snowfall combined with gusty winds
reducing visibility...and snow blowing across roadways.
Christmas night through Saturday. Showers will linger in the cold
air across eastern Nevada through Friday as a very cold air mass
begins to penetrate the Great Basin. An extended northeasterly
upper jet flow will continue to pull in very cold air...leading to
temperatures dropping into the single digits in many areas at
night with high temperatures peaking only in the 20s widespread.
Long term...Saturday night through next Wednesday. The 00z long
range deterministic models are in remarkable agreement this forecast
cycle. Short wave ridge which is expected to provide a pleasant
chilly throughout the County Warning Area Saturday...will have its axis slide well
to the southeast of the County Warning Area by Saturday evening. Looking upstream...
both models are focusing in on a powerful 300 mb 120+ knots jet approaching
the northwest Pacific coast later Saturday night and Sunday. Clouds
will thicken in response to tightening middle level thermal gradient
with some light snow/snow showers breaking out across northern and
north central locations Saturday night/Sunday.
The upper level jet carves out a significant upper level trough over
the western states with a closed low and heights roughly around 540
dm by late Monday. The origin of this system is somewhat moisture
starved thus isolated to scattered probability of precipitation will suffice with this event
through Monday night. The most notable feature with this upper level
trough will bring very cold Arctic air into the County Warning Area as 700 mb
temperatures plummet to between minus 15 and minus 20 degree c Monday
night and Tuesday. Surface temperatures will bottom out mainly in
the single digits above and below zero Tuesday morning and then
struggle in many locations to reach 20 degrees Tuesday afternoon.
As this trough moves into the southern rockies...another short wave
ridge will build into the Great Basin for the New Year Holiday next
Aviation...upper level trough axis is just about along the Nevada-
Utah border with the only remaining cold cloud tops over Elko and
White Pine counties. All taf sites are reporting VFR conditions
at this time. After daybreak expect remaining low level moisture to produce
some MVFR ceilings especially over Elko/White Pine counties along with
some snow showers. VFR ceilings in place at all taf locations tonight.
As for winds...expect gusts 35 to 50 miles per hour confined to eastern
Elko...White Pine and northern Nye counties today. &&
Winter Weather Advisory until 4 PM PST this afternoon for
northern Elko County-south central Elko County-southwest Elko
County-White Pine County.
Winter Weather Advisory until 10 am PST this morning for
northeastern Nye County-northern Lander County and northern
Eureka County-northwestern Nye County-southern Lander County and
southern Eureka County.
Wind Advisory until 4 PM PST this afternoon for southeastern
Winter Storm Warning until 4 PM PST this afternoon for Ruby
Mountains and East Humboldt Range.
Wind Advisory until 4 PM PST this afternoon for northeastern Nye
County-northwestern Nye County.