June 20: battle between the Catalina Eddy and NW wind

This image is a good example of why Southern California forecasting is so difficult. Note the battle between the southerly winds of the Catalina Eddy and the NW winds of the North Pacific High. At present at 10:30AM this is giving C st. and Leo westerly winds and the Cabrillo to Huntington Beach corridor southerly eddy winds.

Why the forecast winds came on weaker than forecast last night:

Friday April 10.

UPDATED AT: 9 AM 11AM and 5PM
The top image below at 9AM to day shows the surface low west of Southern California.You can make out it's counter-clockwise spinning winds. If you look very carefully on the extreme LEFT side of the image you can see the mostly clear skies where the strong NW winds that were suppose to arrive at the Southern California coast this afternoon.

The upper low that is creating this low was modeled to eject eastward over Southern California during the night. Right now it is stalled west of Southern California.

The second image at 11:30 AM shows that the low has barely moved eastward in since dawn. This will keep the most powerful NW wind mostly far out to the west.

But wait... by 5PM the low has actually retrograded and moved westward away from Southern California. This allowed a sliver of NW wind along the Central California coast coast to slip down past Jalama to reach some of the sites as modest upper teen wind late this afternoon. The really good news is that the low really will eject eastward past Southern California and settle in the 4 corners region tomorrow. This will allow the North Pacific High's surface NW winds to finally arrive at the coast. So expect strong wind tomorrow.