Dry Season Solar Panel Cleaning: South Florida's Best Solar Months

South Florida’s dry season, from mid-October to mid-May, includes the strongest solar months of the year. For a typical rooftop array in Fort Lauderdale, March and April out-produce every summer month. More than half of a year’s output comes between mid-October and mid-May. That makes November the most useful time for solar panel cleaning: the panels go into their best stretch with clean glass instead of a summer’s worth of film.

When is the dry season in South Florida?

The National Weather Service in Miami defines the wet season as May 15 through October 15, the part of the year when 60 to 70 percent of the annual rain falls. The rest, from mid-October to mid-May, is the dry season. The air turns less humid, the daily storms stop, and the skies clear. It’s also when hurricane season ends, on November 30.

Which months produce the most solar power in Fort Lauderdale?

We ran an 8-kilowatt rooftop array in Fort Lauderdale, facing south at a 20-degree tilt, through NREL’s PVWatts calculator with its standard loss assumptions. It estimates about 12,700 kilowatt-hours a year. The monthly pattern surprises people who assume summer is solar season:

Months	Estimated output
April	about 1,220 kWh, the best month
March and May	about 1,160 to 1,190 kWh each
June through October	about 1,000 to 1,120 kWh each
November through February	about 910 to 980 kWh each

Summer has the longest days, but it also has the afternoon clouds and storms. Spring has long, clear days before the wet season starts. Add the months on either side, and about 58 percent of the year’s estimated output falls in the dry season.

Your own array will differ with its size, tilt, shade and orientation. The shape of the year should look much the same anywhere from Fort Lauderdale to Boca Raton.

What builds up on the panels in the dry season

Less rain doesn’t mean cleaner panels. It means nothing moves even the loose dust. The South Florida soiling calendar tracks what arrives:

• Dust and salt film accumulate through December and January. Homes near the beach and the Intracoastal, in Deerfield Beach or east Boca, pick up salt every day; see our salt air guide.
• Oak and pine pollen starts in February and peaks in March, right as the array hits its best months.
• Whatever the summer left. Algae along the lower edge of each panel, Saharan dust from June through August, and storm debris are all still there in October unless someone took them off.

Rain wouldn’t have taken them off either; we explain why in does Florida rain clean solar panels.

When to clean for the dry season

November, going in. A clean after hurricane season ends takes off the summer’s dust, algae and storm grit before the clear months begin. It’s one of the two visits on our maintenance plan for exactly this reason.

May, coming out. The second visit, after the pollen tail, clears the spring film before the wet season.

A mid-season visit if your roof needs it. Coastal roofs and roofs with pigeons build up faster than twice a year allows, and a quarterly plan adds visits in between. Seasonal residents often get a clean in March or April before they leave, which lands in the middle of peak pollen and peak production. See how often you need solar panel cleaning in South Florida for how to pick.

Why the timing matters

Film on the glass costs output in proportion to how much sun there is to lose. A film costs the most in the months with the most sun. In South Florida those are March through May, at the end of the dry season, and the dry season as a whole carries more than half the year’s output. Clean glass in November and again after the pollen means the array spends its strongest stretch doing what it was bought to do.

Get a free quote or call (954) 872-1622 to book a November cleaning before the clear months begin.