I'm looking at some more maps and seeing that average peak sun hours may be lower than that 5.7 figure. LA's average may be 4.5.
EDIT: Nope, according to
THIS, you're somewhere around a 5.7 average throughout the year. 6.14 summer - 5.03 in the winter.
THIS website backs the first one up. Now the amount of ENERGY hitting your panels during that time varies as you have already seen. Peak sun hours is just the amount of time for the peak available sun energy to hit your panels. In the summer, that could be 7kWh/m2 per day or half of that in the winter.
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