Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Joaquin Valley - Hanford California
242 am PDT Tuesday Oct 25 2016
weak high pressure will build over the region today and Wednesday
before another Pacific weather system moves in Thursday night and
Friday bringing another chance of rain and snow.
Discussion...radar shows a few echoes across the far northwest
early this morning as a stalled out frontal band remains just to
the north of Merced County. For this morning a slight chance of a
light shower has been left in the forecast for this area as
satellite imagery and forecast models indicate the threat will
continue well into the morning. From this afternoon through
Wednesday night, things look to be dry over the forecast area as
models shift the upper level flow to a more southwest direction in
advance of the next approaching system now located out near
35n/147w. This feature will get entrained in the flow around the
very deep low pressure area near the Queen Charlotte islands
however well to the west another low pressure area is projected to
develop near 32n/145w. This second low is project to move east and
bring the next threat of precipitation to the coast by Thursday
evening with models ejecting it quickly east on Friday.
Give the above scenario, the weather will be dry today through
much of Thursday before it gets wet for what looks like a 12-15
hour window lasting into mid day on Friday. Forecast confidence
beyond Friday is low to say the least as models are in decent
agreement that a deep area of low pressure will move into the
Pacific northwest however whether a front moves deep into central
California or not is questionable. The GFS model brings a frontal
system through much of the area Sunday however the European model
is farther north and affects mainly northern California.
MVFR ceilings with mountain obscurations over the southern Sierra
with local IFR in isolated showers around Yosemite np through 18z
Tuesday. Otherwise, VFR conditions can be expected for the central
California interior during the next 24 hours.
Air quality issues...
The level of certainty for days 1 and 2 is medium.
The level of certainty for days 3 through 7 is low.
Certainty levels include low...medium...and high. Please visit
www.Weather.Gov/hnx/certainty.Php for additional information
an/or to provide feedback.