Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
201 PM PDT Sat Oct 22 2016
a storm system will move over northern California this weekend;
temperatures are expected to lower slightly each day during
Sunday and Monday. After a brief dry period, another storm system
will bring a better chance for rain and higher elevation snow in
central California by late in the week.
Discussion...high pressure has mainly shifted east of the region,
although we remain under a southwest flow aloft. High clouds
continue to move over central California this afternoon, and high
temperatures have been trending slightly higher compared to this
time yesterday. The low pressure trough will be moving inland on
Sunday, so temperatures are expected to start trending downward a
little by Monday. This low pressure system will bring a slight
chance for showers over the mountain areas, although precipitation
amounts are expected to be generally light with this system.
High pressure will rebuild over the Desert Southwest and the
Rocky Mountain regions late Tuesday into Wednesday, so expect a
brief dry and relatively warm period until the next low pressure
system arrives on Thursday. Temperatures will likely remain near
or slightly above average through the middle of the week.
By Thursday, models are generally in fairly decent agreement in
terms of bringing the next low pressure system. This system
appears to have more significant precipitation moving over central
California, and models remain consistent with this feature for the
period during Thursday into Thursday night/Friday morning. The
moisture feed at this time still looks to be subtropical in
origin, so we are not expecting snow levels to lower
There have been some run to run inconsistencies, especially with
the Euro model, for much of Friday and into next Saturday, so did
not change the forecast much during this period. The Euro model is
faster in progressing the low pressure system eastward compared to
the GFS. Confidence is generally medium for the extended period,
although low for Friday and afterward.
VFR conditions will prevail at all terminals through the next 24
Air quality issues...
The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is medium.
Certainty levels include low...medium...and high. Please visit
www.Weather.Gov/hnx/certainty.Php for additional information
an/or to provide feedback.