Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Elko Nevada
257 PM PST Wednesday Jan 28 2015
Synopsis...more above normal temperatures expected this week.
A Great Basin low will move over southern and central Nevada late
in the week bringing precipitation to areas south of Interstate
eighty. Expect a mix of mountain snow and valley rain. Dry weather
will return for the weekend.
Short term...tonight through Saturday. The forecast period
commences with the longwave ridge axis from b.C. To central Nevada.
That said...the precipitable water from the latest sounding at Elko was .48 of an
inch which is 177 percent of normal and it actually felt humid
today.The radar at klrx has been relatively uneventful...but relative humidity
has been well above normal by High Desert standards at wmc and
eko. Expect more above normal afternoon temperatures this forecast
period...with the mean maximum temperature for Elko at 37f the 29th...30th
and 31st...which will be exceeded handily. The main event this
forecast period will be the Great Basin low. Expect the 500 mb center
of circulation to pass south of the lkn County Warning Area with wrap around
moisture steering a fetch of Pacific moisture into southern and
central Nevada. The rmop...is not confident with this system...and
the probability of precipitation may need to be altered again...but generally expecting
the lions share of the quantitative precipitation forecast south of Highway 50 Friday and
Long term...Saturday night through next Wednesday. Still warm for
January with higher precipitable waters than usual this time of year. Hence...any
precipitation will tend toward liquid in the valleys and snow/wet snow in
the mountains. Not expecting much quantitative precipitation forecast over all...apart from very
high ridges in places like Jarbidge...rubies/east humboldts...and
toyabies for example.
Two features offshore will affect the long range forecast. The
models are keying on weak trough which now lies offshore from
Southern California. This trough is has a dry entrainment path from
the tropics but that is closing as it swings east. This is the
trough the models are agreeing on bringing into central and
northeast Nevada beginning late Saturday night/Sunday.
However...there is another feature well into the north central
Pacific which the models want to retrograde west over time. This
giant closed low is actually swinging slowly east over time and not
behaving like the models want it to. The Euro moves it toward the
Aleutians over time and the GFS breaks it up and swings several
short waves into the American interior west. Hence...little
confidence on producing serious precipitation in the long range. Will go
with the agreed upon solution for Sunday through Tuesday with a
potentially slight wet period with probability of precipitation in the slight chance to
upper chance over higher terrain...but mainly over northeast Nevada
with straggling showers over central and eastern Nevada.
Winds do not appear to be wanting to go gangbusters with these waves
and so have left alone.
Aviation...all fields have VFR weather Wednesday afternoon but
clouds are slowly making their way out of the region. Might get some
vicinity fog forming at kwmc keko overnight with potentially MVFR
visibility. Expecting slightly higher drainage winds at kely and
ktph and not expecting fog there. This is a highly unusual situation
for January...however. Confidence in forecasting fog/no fog is not
great. Please stay tuned to amendments.