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Area forecast discussion 
National Weather Service San Diego California
200 PM PDT Tuesday Jul 22 2014

Synopsis...
continued dry and warmer through Friday...with inland temperatures
exceeding seasonal averages by Wednesday. Thursday and Friday are
expected to be the warmest days when temperatures in the inland
areas could be 5 to 10 degrees above seasonal averages. The marine
layer will become shallower...with patchy low clouds and fog near
the coast during the nights and mornings. Inland temperatures will
decrease somewhat for the weekend through early next week as
monsoonal moisture brings higher humidities...some middle and high
clouds...and a slight chance for afternoon showers and thunderstorms
on Sunday.

&&

Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
counties...

Mostly clear this afternoon...except for patches of low clouds over
the coastal waters and a few middle and high clouds drifting in from
the south. Temperatures are generally a few degrees higher than this
time yesterday...except for the San Diego County coastal areas where
they are a few degrees lower due to the marine influence. Expect low
clouds and fog to return to the coastal areas overnight.

A low pressure trough off the California coast and an upper level
high centered over New Mexico is keeping socal under dry south-southwest flow
aloft. Conditions will remain dry as the upper high expands
westward...resulting in progressively higher temperatures through
Thursday. By Wednesday...inland temperatures begin to exceed
seasonal averages and by Thursday they could be 5 to 10 degrees
above seasonal averages. Temperatures stagnate or decrease slightly
for Friday as small amounts of sub-tropical moisture begin to filter
in as the flow aloft turns southeast. This could result in some
cumulus buildups over the mountains Friday afternoon.

Temperatures decrease slightly through the weekend...but remain near
or a little above seasonal averages as monsoonal moisture increases.
Cumulus buildups are likely again Sat afternoon...and deep
convection is possible as the east-West Ridge axis begins to move
north of the region. A tropical wave is expected to move in from the
southeast...bringing a substantial influx of moisture and a slight
chance for showers and thunderstorms over the mountains Sunday afternoon.

For early next week...high pressure aloft will keep temperatures
near or a little above seasonal averages. However...model solutions
diverge with the 12z GFS maintaining higher levels of monsoonal
moisture and the ecm showing significant drying. The dry solution of
the ecm is consistent with recent model runs while the relatively
wet solution of the 12z GFS represents a departure from recent
solutions. Will have to wait and see what kind of consensus the
models can reach regarding levels of moisture.

In the coastal areas...the marine layer will become shallower as
heights rise aloft...with patchy low clouds and fog spreading only a
few miles inland during the nights and mornings.

&&

Aviation...
222030z...coast/valleys...VFR conditions through this evening.
Stratus...with bases around 1000 feet mean sea level and tops near
2000 feet mean sea level...will develop along the coast early
Wednesday morning...and push around 15 statute miles inland by middle
Wednesday morning. Visibility will lower to around 1-3 statute miles
where stratus nears higher terrain. Low clouds will clear towards
the coast by late Wednesday morning. Forecaster confidence of
stratus timing is moderate.

Mountains/deserts...few clouds around 15000 feet and unrestricted
visibility through Wednesday afternoon.

&&

Marine...
130 PM...gusty northwest winds will develop over the outer coastal waters
this afternoon through early Thursday morning. Sustained winds 15 to
20 knots...with gusts to 25 knots are likely. A Small Craft Advisory is in
effect from 2 PM this afternoon through 5 am Thursday.

&&

Sgx watches/warnings/advisories...
California...heat advisory from 11 am Thursday to 9 PM PDT Friday for the
Coachella Valley...Riverside County mountains...San Bernardino
County mountains...San Bernardino and Riverside County
valleys-the inland Empire...San Diego County deserts...San
Diego County mountains.

Pz...Small Craft Advisory for winds from 2 PM this afternoon to 5 am
PDT Thursday for the waters from San Mateo Point to the
Mexican border extending 30 to 60 nm out including San
Clemente Island.

&&

$$

Public...pg
aviation/marine...jjt

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