The mass and heat budgets on the northern California continental shelf between Point Arena and Point Reyes are examined using moored measurements of horizontal water velocity and temperature made during the second Coastal Ocean Dynamics Experiment (CODE 2). Empirical orthogonal functions (EOFs) are employed to identify components of current and temperature variability with scales that are resolved by the observations. A constrained least squares fit to the EOF-filtered data is used to find maps of velocity which conserve mass and maps of temperature which conserve heat integrated over control volumes. The wind during CODE 2 is characterized by strong southward ''events'' separated by ''relaxations'' of the wind. Currents are southward and offshore during events and northward and only slightly onshore during relaxations. Vertical velocity is estimated from the divergence of the mass-conserving horizontal velocity field. Upwelling occurs during wind events, with the strongest upwelling occurring nearshore and just to the south of Point Arena. Downwelling is observed during each relaxation but is too weak to be statistically significant. Water temperature rises gradually during relaxations and drops quickly near the beginning of events. The vertical turbulent heat flux at a depth z is estimated as the residual in the heat budget of a volume bounded by the surface and z after accounting for heat advection and surface heat flux. Statistically significant mixing is found at the beginning of two events and is followed by strong advective cooling. Close to shore, heat is advected primarily in the cross-shore direction, while farther offshore, alongshore advection is also important. The pattern of vertical mixing followed by offshore advection, as observed near shore, is that predicted by two-dimensional models of upwelling which include mixed-layer dynamics. ¿ American Geophysical Union 1988