Flow Separation South of Pt Sal Today

As the Sally Ann and Sounder drove the box patterns,  we first noticed that the flow just west of Pt Sal was to the south.  Then to the south of the Pt running east into the bay were seeing strong surface slicks extending south offshore of Pt Sal indicative of flow separation.  Below is a view north to the point and south down to Vandenburg.

We were doing tow-yo CTD and ADCP surveys through these fronts.  It was quite remarkable how intense the southward flow was and the shift across these boundaries.   An example of this is shown below.  This is the last E-W transect we did south of Pt. Sal.  The top panel shows the top and bottom velocity vectors.  Farther offshore the flow is >30 cm/s to the SSE.   The vertical structure is also interesting w/ a surface front at about time 12.8 hours.   Then farther onshore the flow velocity is much weaker and potentially slightly northward (plot by Derek Grimes)

The CTD tow-yos also show similar type of features.  Here are all the casts from the first and second pass around our Pt Sal box in a 3D view with the point bathymetry embeded.  Note the fronts in the E-W leg south of the point  (note this is in a x-y coordinate system with x in the +east and y in the +north directions – plot by Mike Kovatch).

Then in the afternoon the internal bores really hit the point hard.   The interaction of the flow separation and internal bores will be very interesting to study.