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Area forecast discussion...updated 
National Weather Service Reno Nevada
819 PM PDT Mon Oct 24 2016

quick update to expire the lake wind and wind advisories except
for Lake Tahoe. Winds are diminishing tonight across most valleys
and mid slopes although it will remain locally breezy at times
through the night. The Sierra ridges will continue to gust to near
80 mph overnight with gusts to 40 mph over Lake Tahoe.

As far as the rainfall, it's on track and falling mostly west of a
Susanville to Portola line with amounts up to 1/3" so far. Local
amounts up to 3/4" here, but most areas west of that line will see
it 1/4" to 1/2". Further north and east, lighter amounts with up
to a tenth of an inch. The precip should wind down there after
midnight with a few showers continuing into tomorrow. No other
updates planned at this time.


Previous discussion... /issued 319 PM PDT Mon Oct 24 2016/

low pressure will move through the Pacific northwest and bring
rain to the the northern Sierra and far northwest Nevada tonight.
Gusty winds will persist this evening and overnight. Confidence
continues to increase for a warm and wet system by late Thursday
into Friday with yet another storm possible Sunday.

Short term...

One system is exiting and another approaching as we continue to
stay in an active pattern. A few thunderstorms fired over the
basin and range on the back end of exiting shortwave. These should
exit western Nevada by early this evening. Otherwise, it has been a
dry day with widespread gusty winds. Gusts have been in the 35-40
mph range except for some local gusts approaching 50 mph over
northwest Nevada/northeast California. Ridges continue to gust close to 90

For the near term (tonight through wednesday), incoming system
will focus on northern California with upper level jet and moisture plume
sagging southward into the northern Sierra mainly north of Lake
Tahoe tonight and early Tuesday. Some moderate to occasionally
heavy rainfall is likely from western Plumas into western Lassen
County where the current forecast shows 0.75"-1" accumulation.
Amounts drop off quickly farther south into the Tahoe basin with
only very light rainfall into Mono County along the crest. Snow
levels will be high (8000-9000 feet) and no significant winter
weather impacts are expected. We will continue to see the gusty
winds this evening, but speeds for most valley locations should
begin to Ebb later this evening and overnight.

Upper ridge will amplify Tue-Wed which will pull the moisture tap
to the northwest and leave all areas dry and warmer by Wednesday.
Winds will also decrease although locally breezy conditions will
continue each afternoon in the higher elevations.

For Thursday and Friday, southern portion of splitting east
Pacific trough will approach the Sierra and models have shown
better confidence today. Upper low is far enough south to tap
subtropical moisture as it moves toward California and then ejects into
the Great Basin, as next mid latitude trough drops south out of
the Gulf of Alaska (sunday system). The track is looking best for
the Sierra south of I-80 including Mono County where appreciable
rainfall is becoming likely. Snow levels will remain very high
(mostly 9500-10000 feet) with a warm rain process leading to
efficient precipitation despite its quick movement across the
area. We bumped up pops areawide for Thursday night-Friday with
quantitative precipitation forecast 1"-2" along and west of the Highway 395 corridor from Alpine
County southward into Mono County and up to 1/2" farther east
toward the Highway 95 corridor south of Fallon. This will soak
parts of the region that missed out on rains from the last big
storm. Some rises in creeks and streams are possible and heavy
rain could affect Sierra burn scars. Winds will be much less with
this storm. Hohmann

Long term...Saturday through Monday...

For this weekend, Saturday will be generally dry with temperatures
near average, although a band of moisture spreading across northern
California could produce a few light showers in northeast California.

Another low pressure system remains on track to reach the Sierra and
western Nevada Sunday and Sunday night. This system will move through
rather quickly, although the Sierra and northeast California could receive
decent precip for several hours. For western NV, rain will be more
spotty with shorter duration, with better chances north of US-50.
Snow levels are likely to remain rather high, although not quite as
high compared to the Friday storm. Currently, we are anticipating
snow levels between 7500-8500 feet from Tahoe northward and 8500-
10,000 feet for alpine-Mono counties, possibly dropping by another
500-1000 feet by early Sunday evening or during periods of heavier
precip. A period of breezy conditions with stronger ridge top gusts
is also likely Sunday afternoon and evening as this trough moves

On Monday, another weaker shortwave is indicated on the latest
medium range guidance, which could bring more showers to portions of
the region. At this time the best chance looks to be for areas north
of I-80 in western NV, and from Tahoe northward to western Lassen
County in eastern California. Air mass is likely to be cooler compared to
Sunday, which may allow snow levels to dip near 7000-7500 feet
around Tahoe and 6500 feet for northeast California early Monday. Currently
we are not expecting significant travel impacts due to the
precipitation being light and spotty, but the model guidance has
varied with the strength of these weather systems from one day to
the next. Mjd


Isold tstms over west central Nevada east of US-95 will exit to the east
by 00z. Otherwise, most precip tonight should be limited to
northeast California and near the Sierra crest. Some light -shra may spread
into the Sierra terminals, with less than 25% chance for MVFR cigs
or vsby. For the western Nevada terminals, rain is unlikely with VFR
conditions prevailing although higher peaks could remain obscured.

Gusty S-SW winds around 30-35 kt are expected through early this
evening at the main terminals, with a few higher gusts to 40 kt
possible in and near the Sierra foothills. Out in west-central NV,
gusts are expected to top out in the 25-30 kts range. Sfc winds will
decrease overnight in most areas, but stronger SW winds will
continue in higher elevations with ridge top gusts up to 75 kt. This
will keep turbulent conditions in place, with possible low level wind shear at times
later tonight into Tuesday morning. By Tuesday afternoon, wind gusts
20-25 kt are likely at the main terminals, with local gusts up to 30
kt. Mjd


Rev watches/warnings/advisories...
Nevada...Lake Wind Advisory until 5 am PDT Tuesday for Lake Tahoe in

California...Lake Wind Advisory until 5 am PDT Tuesday for Lake Tahoe in



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