Scientific Forecaster Discussion
fxus66 kmtr 221134
Area forecast discussion
National Weather Service San Francisco Bay area
434 am PDT sun Jul 22 2018
Synopsis...seasonable conditions will remain in place through
Monday. High pressure will build over the region by midweek
bringing hot temperatures to interior areas and in the mountains.
Discussion...as of 3:40 am PDT Sunday...the marine layer has
deepened somewhat to around 1800 feet, and coastal low clouds
appear to be spreading a little farther inland, per satellite
imagery. Similar or slightly cooler high temps are expected today
due to the slightly deeper marine layer and continued onshore
flow. Highs should range from the 60s to mid 70s at the coast, to
the 80s and 90s inland. Not much change is indicated for Monday as
conditions remain fairly similar.
By midweek an upper level ridge will build westward into
California from The Four Corners region which will initiate a
warming trend for the area. The areas expected to be most
affected will be southern and central California, but hot
temperatures are expected to edge into our area as well. In
addition, overnight low temperatures will remain warm in the
higher terrain, thus a heat advisory has been issued for the East
Bay hills as well as the mountains of San Benito and inland
Monterey counties, and the southern Salinas valley beginning
midday Tuesday and extending through Wednesday afternoon. The
ridge will begin to moderate on Thursday with slight cooling
expected for the end of the week.
Aviation...as of 04:34 am PDT Sunday...for 12z tafs. Conditions
currently range from VFR at klvk to LIFR at kmry as stratus
remains along the coast and inland. Clearing expected this morning
around 17z for most areas. Once stratus clears, VFR conditions to
prevail through this evening when another early return is
forecast. Light to moderate onshore winds this afternoon.
Vicinity of ksfo...MVFR to IFR cigs through around 16z-17z.
Confidence on clearing time is low. Westerly winds increasing this
afternoon to 15-20 kt.
Sfo bridge approach...similar to sfo.
Monterey Bay terminals...IFR/LIFR cigs through around 17z before
VFR conditions prevail. Early return of IFR cigs is expected late
this afternoon/early this evening. Generally light winds through
Marine...as of 2:22 am PDT Sunday...generally light winds will
continue across the coastal waters through the rest of the
weekend. Northwesterly winds will then increase through the coming
week. Two long period southerly swells will impact the region
with the first through the weekend and the second arriving early
... Bay from 2 PM
Public forecast: Sims
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