Alameda, Contra Costa, Santa Clara and Santa Cruz are among the counties hosting clinics.
Due to limited supplies of the vaccines, only pregnant women, young children, and people with chronic medical conditions or compromised immune systems will be eligible to receive the vaccine.
Health officials in Alameda County will be holding four clinics Saturday, as well as several more on upcoming Saturdays this month and in December, according to Vanessa Cordova, spokeswoman for the county's Public Health Department.
Only pregnant women, children between six months and four years old, children between five and 18 years old who have chronic medical conditions, and people who live or care for infants less than six months old will be eligible for the vaccine, Cordova said.
Two clinics will be held in Oakland, one at the Lincoln Square Recreation Center at 250 10th St. and another at the Ira Jenkins Recreation Center at 9175 Edes Ave.
A clinic will also be held in Fremont at the Fremont Teen Center, located at 39770 Paseo Padre Parkway, and in Hayward at the Hayward City Hall Rotunda, located at 777 B St. All clinics run from 9 a.m. to 1 p.m., or until the supplies run out.
For later dates and locations of the clinics, visit the department's Web site at www.acphd.org.
Contra Costa Health Services is also hosting a clinic Saturday at the Hilltop Mall in Richmond.
Both the H1N1 and seasonal flu shots will be offered to the same at-risk groups in Contra Costa County, according to Public Health Director Dr. Wendel Brunner.
The clinic will run from 10 a.m. to 3 p.m. in the JC Penney parking lot, located at 2200 Hilltop Mall Road.
Santa Clara County will also be holding an H1N1 vaccine clinic Saturday. That clinic is available to pregnant women, children and young adults between six and 24 years old, people who live with or care for infants under six months old, and people with chronic medical conditions.
The clinic will be held from 9:30 a.m. to 11:30 a.m. at the Expo Hall on the Santa Clara County Fairgrounds, located at 344 Tully Road in San Jose.
In Santa Cruz County, officials will be administering 1,000 doses of the vaccine at a clinic Saturday.
The clinic is scheduled from 2 p.m. to 8 p.m. at the Santa Cruz Health Center, located at 1080 Emeline Ave. Another clinic will be held Nov. 14 at the Watsonville Youth Center, located at 30 Maple St.
Health officials are advising people who may want the vaccine but are not one of the eligible groups to contact their health care providers, since private providers are also receiving a large number of the vaccines. FULL COVERAGE: The latest flu headlines
RESOURCES: Flu info, links and answers