Area forecast discussion
National Weather Service San Diego California
935 am PDT Wednesday Jun 19 2013
Synopsis...
upper level trough will remain in place through this weekend...with
only minor changes in the temperatures and marine layer. For this
reason...expect the night and morning low clouds along the coast and
in the western valleys...and some beach locations may not clear
during the day. Gusty west winds will also develop each afternoon
and evening in the mountains and deserts. High pressure may finally
rebuild by early next week...bringing warmer conditions to the
inland areas.
&&
Discussion...for extreme southwestern California including Orange...
San Diego...western Riverside and southwestern San Bernardino
counties...
Water vapor imagery continues to show a negatively tilted trough is
moving inland across the Pacific northwest and northern California
this morning...with Southern California remaining under the dry
westerly flow aloft. As a result...skies are predominately clear
across the region this morning...with the exception of the low
clouds along the coast. An eddy spun up last night...and the the
12z knkx sounding shows that the marine layer deepen to around 2100
feet deep...with a 10 degree inversion. For this reason...thought
that most of the beaches would see only marginal if any clearing
today...but the current visible imagery shows the southern Orange
County and northern San Diego County coasts clearing as the eddy
drifts off to the southwest. At this point time...think that the
beaches will likely clear for some time today...but the question is
how quickly soon will the low clouds move back into the coast? The
local WRF would suggest during the early evening hours...even though
experience would suggest a little earlier. Otherwise...expect
conditions to be similar to or a little cooler than yesterday.
Gusty west winds will once again develop across the mountains and
deserts this afternoon. The upper level support looks similar to
yesterday...with 850 mb winds ranging between 25 and 30 kts and 30
above ground level winds ranging between 30 and 35 kts. For this reason...have
issued a Wind Advisory for the Banning pass and areas north of
Interstate 10 in the Coachella Valley for this afternoon and evening.
This upper level trough will remain over the west through this
weekend...as several disturbances move through it. As a
result...only expect minor fluctuations in temperatures and the
marine layer over the next several days. An eddy will likely spin
up each night...with low clouds and fog pushing back into the
coastal areas and into the San Diego County valleys. The inland
Empire will remain mostly clear...but some low clouds may sneak into
the outer fringes of the inland Empire each morning. Although the
low clouds will clear back to the coast...some days the beaches may
not see much if any sun. Otherwise...expect locally gusty
conditions to develop in the mountains and deserts each afternoon
and evening.
Models are now in pretty good agreement for early next
week...showing The Four Corners ridge building westward into the
Desert Southwest. However...the European model (ecmwf) is still showing hints of a
weak disturbance along the Southern California by middle week. For
this reason...think the inland areas will likely see a decent
warming trend for Monday through Wednesday...but coastal areas will
continue remain on the cool side...with low clouds.
&&
Aviation...
191530z...coast/valleys...stratus...with bases around 1700 feet mean sea level
and tops near 2300 feet mean sea level...will continue to clear towards the coast
this morning. Low clouds may hug the coast throughout the day due to
a strong inversion over the area. Stratus...with slightly lower tops
and bases...will fill in along the coast late this evening...and
push around 25 sm inland by middle Thursday morning. Visible 2-4 sm br is
expected where stratus nears higher terrain tonight.
Mtns/deserts...westerly wind gusts to 35 knots will develop over mountain
ridges and Desert Mountain slopes this evening through tonight. Locally
strong up/down drafts and low level wind shear are possible north of kpsp.
Otherwise...clear and VFR conditions will continue through Thursday
morning.
&&
Marine...
northwest wind gusts around 20 knots will develop over the outer coastal
waters this afternoon through this evening. Conditions are expected
to remain below Small Craft Advisory criteria.
Some of the highest tides of the year are forecast this
weekend...with tidal swings around 9 feet possible. Although surf is
expected to be low to moderate...minor coastal flooding could be
possible. Strong rip currents are forecast throughout the weekend.
&&
Sgx watches/warnings/advisories...
California...Wind Advisory from 2 PM this afternoon to 3 am PDT Thursday for
the Coachella Valley.
Pz...none.
&&
$$
Public...Palmer
aviation/marine...jjt
