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223 PM PDT Sun May 24 2015

Warmer temperatures with showers and thunderstorms expected this
weekend into mid next week, mainly over mountains. High pressure
dries things out by late in the week.


.Discussion (Today through Wednesday)... 

Today the region will be between high pressure out over the
pacific and low pressure the Rockies. Shower and thunderstorm
chances will continue over the mountains into the evening hours.
Any storms that do form should be located towards the crest.
Decent delta breeze will help to cool temperatures off fairly well
this evening for the Sacramento region into the 60s by 9 pm.
Further north it will take longer with Redding not cooling into
the 60s until after midnight.

On Monday another low pressure area will move over the Pacific
Northwest with the tail end of the trough dipping down into the
far northern part of the state. This will continue the shower and
thunderstorm activity over the mountains and bring a slight chance
for some activity to the far northern end of the central valley.

On Tuesday the low over the Pacific Northwest will move slightly 
eastward. This should result in less precipitation over the 
interior but still some isolated activity remaining over the 
mountains. The low does not moves that far from Tuesday into
Wednesday so expect similar chances for thunderstorms over the
mountains. Temperatures will also be warming up into the 80s to
lower 90s by midweek.

.Extended Discussion (Thursday through Sunday)

Ridge of high pressure over Northern California Thursday and
Friday bringing warmer temperatures and decreased threat of
showers and thunderstorms over the mountains. High temperatures are
expected to reach in the upper 80s to mid 90s in the Valley and
60s and 70s in the mountains, which is generally around 5 to 10
degrees above normal for the end of May. The ridge shifts east on
Saturday as an upper level trough approaches the west coast. The
trough will bring an increase in onshore flow and cooler
temperatures for the weekend. Temperatures are expected to cool
to near normal for this time of year on Sunday with highs in the
low to mid 80s in the Valley and mid 50s to low 70s in the



General VFR conditions expected next 24 hours except areas of
MVFR across the higher elevations of the northern Sierra Nevada.
Scattered showers and isolated thunderstorms over the Coast Range
and northern Sierra Nevada 22Z-03Z. Local southwesterly wind gusts
to 35 kts through the Delta.


.STO Watches/Warnings/Advisories...


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