North Bay Mountains Severe Watches & Warnings NOAA Weather Radio

Watches & Warnings

Heat Advisory
Issued: 3:56 AM PDT Jun. 23, 2018 – National Weather Service

... Heat advisory remains in effect from 11 am this morning to
8 PM PDT this evening...

* timing... 11 am to 8 PM Saturday.

* Locations... most of the inland greater San Francisco Bay area
(excluding coastal areas), inland Monterey County, and inland
San Benito County. For the San Francisco Bay shoreline... main
heat risk is primarily from Redwood City to Cupertino.

* Temperatures... widespread temperatures in the mid 90s to low
100s in the impacted areas are expected. The hottest inland
locations such as Pinnacles National Park and the extreme inland
portions of Napa, Sonoma, and possibly Contra Costa counties may
surpass 105 degrees. The cities of San Francisco and Oakland are
excluded from this heat advisory, but will be very warm this
afternoon with highs expected in the mid to upper 80s. San
Jose, which is included in the advisory, is forecast reach the
mid to upper 90s. For the San Francisco Bay shoreline, the main
heat risks are generally from Redwood City to Cupertino where
triple digit temperatures are forecast, while other areas of the
shoreline will be noticeably cooler.

* Impacts... moderate to high risk of heat related illness,
especially for vulnerable populations during the day Saturday.
Increased number of visitors to coastal communities and
beaches to escape heat, potentially resulting in increased
water rescues. Exacerbation of critical fire weather
conditions, especially in the north and East Bay hills and

Precautionary/preparedness actions...

A heat advisory means that a period of hot temperatures is
expected. Hot temperatures will create a situation in which heat
illnesses are possible. Drink plenty of fluids... stay in an air-
conditioned room... stay out of the sun... and check up on
relatives and neighbors.

Fire Weather Warning
Issued: 3:59 AM PDT Jun. 23, 2018 – National Weather Service

... Red flag warning remains in effect from 11 am this morning to
8 PM PDT Sunday for gusty northerly winds and low relative
humidity for the North Bay mountains and East Bay hills...

* wind... northerly winds of 15 to 30 mph with gusts to 40 mph.
Isolated highest terrain could see locally higher winds.

* Humidity... minimum humidity readings of 10 to 20% will be
common during the day, with the driest locations dropping
into the single digit range during the warmest, driest,
windiest times of the day. Overnight humidity recoveries will
be poor and less than 30%.

* Highest threat... elevations above 1000 feet, especially in
the extreme northern and eastern portions of the North Bay
mountains and East Bay hills

* impacts... any fires that develop will likely spread rapidly.
Outdoor burning or other activities that may lead to fire
creation is not recommended.

A red flag warning means that critical fire weather conditions
are either occurring now... or will shortly. A combination of
strong winds... low relative humidity... and warm temperatures can
contribute to extreme fire behavior.