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Area forecast discussion 
National Weather Service San Francisco Bay area
900 PM PDT Tuesday Sep 30 2014

Synopsis...building high pressure over the region will result in
a drying and warming trend through late in the week. Daytime
temperatures will be as much as 10 to 15 degrees above seasonal
averages by the end of the week.

&&

Discussion...as of 9:00 PM PDT Tuesday...as a northerly surface
pressure gradient began to tighten across the state...skies
cleared from north to south with sunny conditions over most of the
district all day. There was a stubborn patch of stratus hanging
onto the Monterey peninsula through most of the day...but it
finally cleared out before sunset. High temperatures today were
warmer than yesterday across the northern two thirds of the
district...and a few degrees cooler across the southern areas.
Highs ranged from the 60s at the immediate coastline to the 70s
to middle 80s inland. The surface pressure gradient from acv to sfo
has increased to 6.6 mb...from 3.1 mb 24 hours ago. The gradient
between wmc and sfo has also increased to 5.3 mb...while the
onshore gradient between sfo and SAC has lessened to 1.1 mb.

Expect clear skies tonight with locally breezy conditions in the
hills...particularly in the North Bay. The winds should taper off
somewhat during the day but remain offshore through Friday. The
building ridge of high pressure...in addition to offshore
flow...will allow high temperatures to warm well above seasonal
normals...especially by Thursday and Friday. Highs by then are
forecast to warm into the 80s at the coast...to the 80s and 90s
across the district...with the warmest interior locations topping
out around 100 degrees. The ridge is forecast to weaken somewhat by
the weekend...however not by much...thus warm conditions will
persist through the weekend. Weak onshore flow is expected to
return by early next week for cooler temperatures along the
coast...but warm conditions will persist inland through early next
week.

&&

Fire weather...as of 2:15 PM PDT Tuesday...offshore flow will
develop over the region tonight and early Wednesday. This is a
typical pattern where winds will be strongest over the north and East Bay
hills right around sunrise Wednesday morning. Would not be
surprised if gusts up to 40 miles per hour were observed over the highest
peaks. Initially tonight...humidities will be high but rapidly
plummet as the offshore flow Cranks up. Winds will gradually
weaken through day Wednesday allowing for further drying in the
boundary layer. Offshore flow continues into the weekend producing
poor night time recoveries...but winds will be light. Despite the
offshore winds and poor recoveries a red flag warning will not be
issued due to the wet fuels. The recent rains have left fine fuels
moist for this time of year. It will take some time to dry things
back out. Fuels may return to critical levels later this week.
None the less...a prolonged period of hot and dry conditions are
expected middle week lasting into the weekend. Stay tuned.

&&

Aviation...as of 9:00 PM PDT Tuesday...the norther;y surface
pressure gradient is tightening and skies have cleared across the
district. VFR condtitions expected.

Vicinity of ksfo...VFR.

Ksfo bridge approach...similar to ksfo.

Monterey Bay area terminals...VFR.

&&

Climate...record high temperatures for Wednesday through Friday
(10/1 to 10/3) along with the most recent date it occurred.

Sf Bay area
location.................10/1...........10/2............10/3...
Kentfield................97/2012.......100/2012.........99/2012
San Rafael..............104/1980.......106/1980........105/1980
Napa....................106/1980.......102/1980........103/1917
San Francisco............97/1980........96/1980.........97/1985
sfo Airport..............97/1980........96/1980.........94/1985
Oakland (downtown)......103/1980.......103/1980........100/1985
Oakland Airport..........94/1952........98/1980.........95/1985
Richmond.................99/1980.......100/1980.........97/2012
Livermore...............102/1952.......106/1980........106/1980
Moffett field............93/1980........95/2012.........97/1985
San Jose.................97/1980........96/2012.........97/1985
Gilroy..................104/2001.......107/1980........106/1980

Monterey Bay area
location.................10/1...........10/2............10/3...
Monterey................103/1980.......101/1980.........96/1985
Santa Cruz..............102/1965.......102/1980........102/1980
Salinas.................104/1980.......100/1980.........97/1985
Salinas Airport.........105/1980.......103/1980.........99/1985
King City...............109/1980.......107/1980........102/1980

&&

Marine...as of 08:13 PM PDT Tuesday...moderate northwest winds
will continue over the coastal waters through tomorrow. Winds
become light Wednesday night through the rest of the week as high
pressure builds over the Great Basin.

&&

Mtr watches/warnings/advisories...
... Reyes to Pigeon pt 0-10 nm until 2 am
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm until 2 am
Small Craft Advisory...pt Arena to pt Reyes 10-60 nm
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm
Small Craft Advisory...Pigeon pt to pt pinos 10-60 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 10-60 nm
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm until 3 am
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm until 3 am

&&

$$

Public forecast: Sims
aviation/marine: Sims
climate: Bell
fire weather: mm

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