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SunnyDays

ERA5 almanac — 8 years of real data

Orlando in May

Orlando in May is historically a poor month for sun: only 30% of days clear across 8 years (n=248, avg high 87°F). Historical average, not a forecast.

What you are reading: 8-year historical averages from the ERA5 reanalysis, not a forecast. A month that is historically 90% clear can still be overcast on your specific trip. For this week’s actual forecast, see the live Orlando page. Both can be true at once: “historically strong in this month; this particular week is not.” We label which is which.

Early vs. Late May

Clear-sky percentage for Orlando in May, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early May
1st–15th		 32% n=120 87°F
Late May
16th–end		 29% n=128 87°F
Full month average 30% n=248 87°F

Sunshine & warmth in May

A second measure using actual sunshine hours (ERA5 sunshine_duration), not the daily weather code. A Lowcountry day with 12 hours of sun and a 25-minute afternoon storm is counted below as a warm, sunny day — because it was. How we define this.

Sunshine-based metrics for Orlando in May. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early May
1st–15th		 92% n=120
Late May
16th–end		 89% n=128
Full month average 90% n=248
12.8 h median sunshine per day 87% of days exceed 8 h sunshine 46% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 30%. Sunshine-based “warm & sunny”: 90%. The 60-point gap is from brief afternoon convective storms that stamp the whole day as “rain” in the WMO code but leave the bulk of the sunshine untouched.

Bottom line

Orlando is mostly overcast in May historically: only 30% of days are clear across 8 years (n=248), avg high 87°F. Most visitors this month will see more clouds than sun.

Every month in Orlando

Compare across all months with data. Numbers are historical clear-sky %.

Historical clear-sky % for Orlando, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 20% n=248 All destinations →
February 33% n=226 All destinations →
March 45% n=248 All destinations →
April 44% n=240 All destinations →
May ← this page 30% n=248 All destinations →
June 7% n=240 All destinations →
July 2% n=248 All destinations →
August 3% n=248 All destinations →
September 10% n=240 All destinations →
October 30% n=248 All destinations →
November 32% n=240 All destinations →
December 26% n=248 All destinations →

All percentages are historical averages from the ERA5 reanalysis via Open-Meteo, 8 full years (2018–2025). “Clear” means avg high ≥ 72 °F, precipitation < 1 mm, and a non-precipitation weather code. This is history, not a forecast. The live 7-day outlook for any destination is on its own page and may differ from the long-run average. Data from Open-Meteo.