Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Reno Nevada
256 am PST sun Feb 14 2016
High pressure near the West Coast will keep above average
temperatures and generally light winds into early next week, except
for some stronger gusts in higher elevations on Sunday. A fast
moving storm will bring a return of wintry conditions Wednesday and
Thursday with gusty winds...rain...and mountain snow.
High pressure remains over the dominant weather feature for the
southwestern US with northeastern California and western Nevada on
the periphery of the ridge. A passing shortwave will bring some
low chances of rain showers to the Surprise Valley and northern
Washoe County today. Elsewhere, conditions will remain
unseasonably mild with generally light winds. The exception will
be some stronger easterly ridge gusts resulting from a tighter
gradient between the passing shortwave and strengthening thermal
low over the Central Valley of California. Gusts 50 to 65 miles per hour
will be possible over the ridges with the stronger gusts occurring
from Alpine County through Mono County.
Otherwise, temperatures remain warm with highs in the 50s to near
60 for Sierra valleys and low to middle 60s for western Nevada. There
is potential for some locations to approach 70 on Tuesday, but it
will depend on how Well Valley inversions mix. Winds will
decrease as the pressure gradient relaxes and as the upper ridge
shifts over the Sierra. Boyd
Long term...Wednesday through Saturday...
Confidence is increasing in a fast moving medium storm system for
Wednesday-Thursday with a period of wind to kick things off Wednesday-Wednesday evening
followed by a period of precipitation Wednesday ngt-Thu. Only minor
changes were made to the ongoing forecast including raising winds
and probability of precipitation another notch.
For Wednesday, winds aloft and surface gradients increase through
the day as 700mb winds are still forecast to reach 60-65kt. Model
soundings continue to show a descending warm layer which puts an
inversion/stable layer down to ridge level for a few hours late
Wednesday afternoon and early evening. While there is not a distinct
wind reversal as is common in downslope wind events, models are
probably not picking the signature up due to the progressive nature
of this system. Widespread winds of 40-50 miles per hour are likely for the
Tahoe basin and Highway 395 corridor by Wednesday afternoon with a short
duration of stronger winds possible.
By Wednesday night into Thursday, precipitation will push into
northern California/Nevada with a burst of moderate to heavy snow likely in the
Sierra, and a mix of rain/snow for the lower elevations of western
Nevada and northeastern California. Snow levels are likely to start
rather high, near or above 7500 feet Wednesday evening but fall
abruptly overnight as the cold front passes. Travel conditions in
the Sierra will likely deteriorate quickly Wednesday night. Although
the short duration of this event will limit overall snow totals,
rapid snow accumulations could lead to significant travel impacts
and possible white-out conditions across the Sierra into the
Thursday morning commute.
By early Thursday morning, rain may change to snow around Reno-
Carson City and eastward along I-80 and US 50, with light
accumulations possible in the foothills. Accumulations are still
looking unlikely below 5000 feet. Precipitation should taper off to
showers and end during the day most areas, although showers may
linger in the northern Sierra into the evening. Breezy southwest to
west winds will persist behind the front through the day Thursday.
After a mild day Wednesday, temperatures will fall to seasonal
normals for Thursday and only slowly warm Fri-Sat. Heights will
rebound as we head into the weekend although a weak system may brush
northern areas where a slight chance of showers was maintained. We
will continue to see periods of middle and high level clouds. There are
indications that the ridge will strengthen early next week.
VFR conditions expected through the Holiday weekend with areas of
middle and high cloud cover especially north of I-80. Very light rain
showers possible this morning near the Surprise Valley. Patchy
shallow fzfg is possible around ktrk through 14z although high
clouds will keep it spotty and brief (about 20 percent probability).
Generally light surface winds expected through Monday, except for a short
period of increased north winds this afternoon-early evening with gusts
15-20 knots possible at the main terminals. Stronger ridge top gusts up
to 50 knots could lead to some turbulence this afternoon-evening near the
For more information from the National Weather Service visit...
http://weather.Gov/Reno (all lower case)