Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service San Francisco Bay area
1043 PM PDT Tuesday Jun 30 2015

Synopsis...hot weather expected once again tomorrow...especially
across inland portions of the forecast area. Cooler temperatures
are anticipated Thursday through Sunday. Upper level moisture
will also make its way toward our area Wednesday and Thursday
which could lead to a few showers and isolated thunderstorms
mainly over the mountains and interior valleys.

&&

Discussion...as of 8:45 PM PDT Tuesday...upper level high over
Utah and Nevada continues to build westward into California. This
brought an additional 10 to 15 degrees of warming over the
interior valleys today. Bradley in southern Monterey County
reached 109 while Livermore reached 108. Gilroy was the only
record today at 103. Coastal areas were much cooler thanks to a
shallow marine layer but even those areas saw more sun than usual
and warmed up as much as several degrees over Monday.

More hot weather is expected Wednesday. Southeast flow aloft will
bring some monsoonal moisture into the southern part of the County Warning Area.
There is a slight chance of showers or thunderstorms mainly over
the hills of Monterey and San Benito counties Wednesday afternoon.
By early evening the showers threat extends into the Santa Cruz
Mountains. Humidities are expected to be higher on Wednesday so
the heat index could be a little higher. In other words assuming
temperatures will be as hot as Tuesday it may actually feel a
bit hotter. A heat advisory is in effect for Wednesday.

The upper high will move northwest on Thursday bringing cooler
temperatures to the area. Moisture will spread further north
Thursday so slight shower chances will extend over most of the
mountains and inland areas of the County Warning Area. Currently expecting about a
5-10 degree cooldown on Thursday.

The upper high will weaken and shift east over the weekend.
The marine layer will deepen and moisture will shift eastward out
of the area. This will bring a little more cooling to the area
over the weekend.

&&

Aviation...as of 10:43 PM PDT Tuesday... high pressure over the
area will maintain mainly clear conditions across area terminals
and will continue to compress the marine layer. Coastal terminals
such as kmry...ksns...khaf...kwvi.Will be the only terminals to
see ceilings tonight. The shallow marine layer will keep low clouds
confined to the coastline. Light onshore flow will continue
through the forecast period.

Vicinity of ksfo... VFR and light winds

Ksfo bridge approach... similar to ksfo.

Monterey Bay area terminals...LIFR ceilings will continue through the
night with clearing expected around 16z Wednesday. Light and
variable winds expected overnight.

&&

Climate...record highs for June 30 and July 1 for selected
locations.

Sf Bay area.................June 30............July 1
Kentfield..................106/1972...........103/1996
San Rafael..................98/1999............99/1991
Napa.......................105/1972...........103/1972
San Francisco...............93/1996............92/1991
sfo Airport.................92/1996............99/1985
Oakland downtown............90/1972............92/1984
Oakland Airport.............90/1950............90/1985
Richmond....................91/1996............97/1985
Livermore..................112/1972...........110/1950
Mountain View...............91/1972............97/1985
San Jose...................100/1996...........102/1985
Gilroy......................98/1999...........108/1972

Monterey Bay area............June 30............July 1
Monterey....................89/1996............96/1985
Santa Cruz..................98/1996............99/1970
Salinas.....................94/1996............85/1996
Salinas Airport.............97/1996............88/1991
King City..................109/1950...........105/1985

&&

Marine...as of 9:00 PM PDT Tuesday...high pressure over the
region will maintain light winds and seas across the coastal
waters through the forecast period. Westerly winds will turn to
the southwest during the later half of the week as the pattern
shifts over the region.

&&

Mtr watches/warnings/advisories...
... Advisory...North Bay area...East Bay area and the
Santa Clara Valley.
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm until 3 am

&&

$$

Public forecast: west pi
aviation: CW
marine: CW
climate: Bell



Visit US at www.Weather.Gov/sanfrancisco

Follow US on facebook and twitter at:
www.Facebook.Com/nwsbayarea
www.Twitter.Com/nwsbayarea

National Weather Service Glossary of Abbreviations