Forecast.solar almost 3x over actual production

I have no idea what is happening here - perfectly clear day in southern California:


My system has 3 arrays all with 400W panels and 330W microinverters:

  1. 11x 400W panels on top of my flat-roof garage. Entered as array 4400W, invert 3630W
  2. 8x 400W panels facing south (az=180), with decl 25 deg. Entered as array 3200W, invert 2640W
  3. 8x 400W panels facing norht (az=0), with decl 25 deg. Entered as array 3200W, invert 2640W

I have this set up as 3 entries in the integration and then check the 3 boxes in the energy dashboard.

Even if I take my best performing panel and multiply by 27, I don’t get the production that forecst.solar is forecasting.

It’s like this every day - I have double and tripple checked everything. How can I troubleshoot this??