The top graph shows the cumulative power output of all panels, measured by taking the maximum power points given by the IV-curve tracer. The bottom graph shows the power output on the AC side, after the inverters.
The irradiance is measured using various pyranometers (both global and in-plane with the solar panels) and the spectrum is measured using a spectroradiometer (in-plane). The dashed plots in the top figure are calculated for clear sky irradiance (using the Ineichen-Perez model) and the dashed spectrum in the bottom figure represents the ASTM AM1.5 spectrum.
These graphs represent various atmospheric variables that are measured by the weather station. The color of the bars in the bottom figure show what kind of precipitation was measured, averaged over that hour of measurements; dark blue means all liquid precipitation and white means all solid (snow/hail).
The latest pictures taken by the webcam and cloudcam are shown here. Pressing the play button will show a timelapse made of images of the previous day.