Officials of the California State University and Community College districts say they're preparing for budget cuts.
If state tax revenues fall below expected estimates, that will trigger automatic cuts to education and social services.
Campuses would be forced to further reduce course offerings and summer sessions, potentially turning away hundreds of thousands of students, officials said.
The 23-campus CSU system has already lost $650 million and the 112-campus community college system have lost $400 million.
The Cal State system, which has 412,000 students, stands to lose an additional $100 million if the midyear cuts are triggered, which would likely result in fewer course sections, fewer instructors and larger class sizes, CSU Chancellor Charles Reed said.
The community college system, which served 2.75 million students last year, would lose an additional $72 million and raise fees to $46 per unit if midyear cuts are triggered.
The Associated Press contributed to this report.