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Area forecast discussion 
National Weather Service San Diego California
925 am PDT Friday Oct 9 2015 will be a hot day as high pressure builds over
central California. Weak offshore flow will produce gusty east winds
in the passes through Saturday morning. Saturday will be another
very warm day with abnormally high temperatures for middle October.
Minor cooling Sunday. Gradual cooling next week with a chance for
showers Wednesday through Friday as a low pressure system off the
Southern California coast slowly moves inland.


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

At 8 am Lindbergh Field had already reached the average high for the
day...73. This puts in perspective just how unseasonably hot it will
get today. Temperatures this morning were running several degrees
higher than yesterday all across the region. In contrast...the
dewpoints were several degrees lower. A heat advisory is in effect
until 8 PM today west of the mountains where the heating of this
warm...dry airmass will be accentuated by downslope adiabatic warming
from increasing offshore flow. The pressure gradients are trending
more strongly offshore this morning and will produce gusty NE winds
of 15-25 miles per hour through the passes and into the valleys this afternoon
through Saturday morning. Temperatures will maximum out above 100
degrees in the inland areas and above 90 in many coastal

Saturday will be another very warm day. Models have been trending
warmer with each run...and it is looking like it will be nearly as
hot as today in some areas. The day will start out quite warm with
temperatures in the middle 60s to middle 70s in most areas west of the
mountains. The overnight low at Lindbergh Field may equal the
average high for the day (73). I will bump up temperatures a degree
or two on Saturday which will bring it close to heat advisory levels.

*** From previous discussion ***

It will remain above normal temperature wise through much of next
week. This will be due to residual warm airmass and a slow
encroachment of higher moisture air into our region from the
south...beginning Sunday. Moisture increasing should bring a cumulus
field to the mountains Sunday and Monday and maybe a few mountaintop
showers especially by Tuesday afternoon. Have removed mention of
precipitation all other areas for Tuesday and Tuesday night as the models
have now shown run to run agreement in slowing down the approaching
cutoff low to the socal coast around middle next week. This is still a
lower confidence forecast due to the difficulty in forecasting a
cutoff low without much direction one way or another. Also...the
models are now in disagreement whether the low core will hold
together or possibly unravel a bit into an open wave by the time it
passes back over Southern California or northern Baja California. The ec and
its ensemble members continue to show better run to run continuity
and are more progressive with the cutoff low to move it inland
towards the end of next week while the GFS is having a more
difficult time latching onto much continuity. Either way it is now
looking like the better chance for precipitation will be towards the
end of next week compared to previous forecasts.


Aviation... 091500...unrestricted visible and few-scattered clouds at or above above
20000 feet feet mean sea level will continue through Saturday morning. 20-25 knots
easterly wind gusts over mountain ridges and coastal foothills will
create moderate-strong uddfs over and west of the mountains...with strongest
winds through this afternoon and again late tonight and Saturday


Marine... 800 hazardous marine weather is expected through


Beaches... 800 am...buoys reports indicate that the long-period
southwest swell is coming in higher than predicted by the wave watch around 3 feet/20 seconds currently. Surfline reports that the
swell is producing 4 to 6 foot surf in Orange County...and 3 to 5
foot surf in northern San Diego County this morning. Given the buoy
and surf trends...the beach hazards statement has been moved up to
start this morning and extended through early Sunday evening. The
swell will continue high through Saturday...and lower slightly on
Sunday. Strong rip currents and elevated surf of 3 to 6 feet with
local sets to 7 feet at southwest facing beaches will continue
through the Holiday weekend. For further details...see the surf
forecast...laxsrfsgx...and the beach hazards statement...laxcfwsgx.


Skywarn... Skywarn activation will not be needed today.


Sgx watches/warnings/advisories...
California...heat advisory from 10 am this morning to 8 PM PDT this evening
for Orange County coastal areas-Orange County inland areas-
San Bernardino and Riverside County valleys-the inland
Empire-San Diego County coastal areas-San Diego County
valleys-Santa Ana Mountains and foothills.

Beach hazards statement through Sunday evening for
Orange County coastal areas-San Diego County coastal areas.




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