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Area forecast discussion 
National Weather Service Sacramento California
330 am PDT sun Jul 24 2016

Synopsis...
dry with a gradual warming trend through the week. Triple digit
heat expected in the Central Valley with high temperatures well
above normal.

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Discussion...
models show upper troughing over norcal will slowly deepen during
the next 24 hours. Little impact expected on heat today though as
850mb temps actually increase a degree or two. With morning temps
running upwards of 12 degrees warmer than yesterday at this time,
expect highs today will be near or several degrees warmer than
Saturday. This means widespread triple digit heat will once occur
across the Central Valley with highs ranging from 100 to around
107, hottest in the northern SAC valley.

Marine layer is currently below 1000 feet this morning but
expected to deepen tonight into Monday. Delta breeze also forecast
to become moderate to strong tonight. Guidance showing slight
cooling for Monday, greatest near Delta influenced areas where
highs expected in the 90s.

Upper ridging from the desert SW expands westward over California
and strengthens Tuesday into Thursday. This will result in more
significant warming with highs from around 103 to 111 in the
Central Valley, hottest in the northern SAC valley. Max
temperatures expected to be upwards of 10 plus degrees above
normal next week with some locations in the northern SAC valley
approaching record values Thursday.

Pch

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Extended discussion (thursday through sunday)

Strong high pressure over the western U.S. For above normal
temperatures through the end of the week. The warmest days look
to be Thursday and Friday when high temperatures are forecast to
reach to between 5 and 10 degrees above season normals. This puts
daytime highs in the Redding area at around 110 degrees. Very low
humidity will exist during this time as well with afternoon
minimum relative humidity values mainly in the teens to single digits. Although
this will increase fire danger, at least winds should be generally
light under the ridge. Models hint at a weak trough or low forming
off the coast around Friday. GFS puts this low close enough to the
coast to start drawing monsoon moisture northward up the Sierra
and into the northern mountains painting precipitation over the
mountains Friday afternoon and evening. European model (ecmwf) and Gem models have
different solutions however keeping any precipitation south and
east of the County Warning Area. Will go with drier majority as GFS seems to be an
outlier for now. Troughing along the West Coast brings a slight
cooling trend next Saturday with increased onshore flow and cooler
airmass bringing more cooling next Sunday. If models persist with
this track then daytime highs could be back down to year normal by
the start of next week.

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Aviation...

VFR conditions next 24 hours. Winds generally below 15 knots
except gusts to 30 knots in the Delta.

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Sto watches/warnings/advisories...
none.
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