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FXUS66 KSTO 302135

235 PM PDT Wed Jul 30 2014

Another day of Sierra crest showers and thunderstorms tomorrow
(less coverage than today)...when a drying trend. Then a return
to Sierra showers and t-storms early/mid week next week.


Activity started pretty early today with showers and
thunderstorms along highest terrain from Near Plumas county all
the way south to Tuolumne County. Expect this activity to continue
off and on this afternoon but probably end a bit quicker than
normal by early afternoon as latest moisture plume pushes off to
the east. HRRR hinting at some weak possible returns in valley
near there is some mid level instability in the
area...but rally lacking a trigger for valley and should result in

Thursday...still some instability lingering around highest terrain
for isolated activity...less than today...again confined to crest.

Friday and Saturday...westerly flow pushes moisture and
instability out of area for dry weather. Should see temperatures
at to slightly above normal during this time. Rasch


.Extended Discussion (Sunday through Wednesday)

Upper ridge positioned over the Intermountain West Sunday as weak
upper trough moves through NorCal. Increased mid-level
southwesterly flow Sunday will keep the threat of afternoon
thunderstorms outside of the forecast area with only a slight
chance over the higher Sierra Nevada, south of Highway 50, on
Monday. Models then depict upper ridging from the Desert SW
rebuilding northwestward over Interior NorCal next week. Mid-level
flow begins to turn more southerly Tue and southeasterly Wed with
another slug of monsoonal moisture working its way into the
forecast area. Threat of afternoon thunderstorms expands
northward along the Sierra Tuesday, through Western Plumas into
the Shasta and coastal mountains Wednesday. Near normal high
temperatures expected through early next week then warming upwards
of 5 degrees above normal Wednesday.



Upr rdg movs E as SWly flow alf with EPAC upr trof incrs Thu. Isold
tstms poss ovr hyr mtn trrn of the Cstl rnge, Shasta, Plumas, and
Siernev thru 05z Thu otrw VFR conds ovr Intr NorCal nxt 24 hrs.
Isold SWly sfc wnd gsts to 25 kts poss ovr hyr mtn trnn and thru
Delta aftns into eves.


.STO Watches/Warnings/Advisories...


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