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Area forecast discussion
National Weather Service Sacramento California
259 PM PDT sun Oct 13 2019

Synopsis...
quiet weather is expected early next week. Near average
temperatures, then cooler than normal temperatures mid to late
week. A weather system could bring a chance of showers midweek.

Discussion...
afternoon temperatures are similar to yesterday across interior
norcal with valley locations expected to top out in the upper 70s
to low 80s and the mountains in the 50s to 60s. A weak upper
level trough is pushing through norcal today. The only impact from
this is high cloud cover and continued below normal overnight
temperatures. Chilly temperatures are expected most nights this
week. Valley lows will be in the low to mid 40s with 20s to 40s
likely in the mountains. Wildfire smoke continues to cause hazy
skies over portions of norcal today. Most smoke is expected to
remain over or east of the Sierra, though some smoke could make it
into the valley.

The weak trough pushes east Monday, bringing brief ridging over
norcal through Tuesday. Quiet weather will continue with near to
slightly below normal temperatures and sunny skies. A stronger
low pressure system approaches the West Coast midweek that brings
a chance of rain to norcal Wednesday night through early Thursday.
Agreement among ensemble models is fairly low at this time. The
gefs continues with a more northern trajectory, keeping
precipitation mainly to the northern coastal mountains and Shasta
County area. The Euro ensemble is still trending deeper, bringing
precipitation down through the northern Sierra and foothills and
possibly into the valley. Hec

&&

Extended discussion (thursday through sunday)...
a weak shortwave trough passes to the east of the state on
Thursday leaving zonal flow over norcal for most of the extended
period. Shortwave troughs moving through this zonal flow will
bring the threat of showers to the northern mountains on occasion,
but confidence in timing and strength of these systems is low at
this time. Most of the forecast area will remain under dry and
cool conditions with daytime highs remaining well below normal
going into the weekend. Upper ridging is forecast to start
rebuilding over the West Coast early next week for a start of a
warming trend.

&&

Aviation...
quiet weather will continue across northern California leaving
taf sites with VFR conditions for the next 24 hours. Winds will
generally be below 12 knots.

&&

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