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SunnyDays

ERA5 almanac — 8 years of real data

Wilmington in May

Wilmington in May: 40% of days see measurable rain, 80°F average high, 34% of days historically clear (n=248, ERA5 2018–2025).

Wilmington in May is historically a poor month for sun: only 34% of days clear across 8 years (n=248, avg high 80°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 Wilmington 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 Wilmington 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		 35% n=120 80°F
Late May
16th–end		 33% n=128 80°F
Full month average 34% n=248 80°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 Wilmington 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		 77% n=120
Late May
16th–end		 86% n=128
Full month average 82% n=248
12.6 h median sunshine per day 84% of days exceed 8 h sunshine 40% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 34%. Sunshine-based “warm & sunny”: 82%. The 48-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

Wilmington is mostly overcast in May historically: only 34% of days are clear across 8 years (n=248), avg high 80°F. Most visitors this month will see more clouds than sun.

Every month in Wilmington

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

Historical clear-sky % for Wilmington, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 1% n=248 All destinations →
February 7% n=226 All destinations →
March 12% n=248 All destinations →
April 32% n=240 All destinations →
May ← this page 34% n=248 All destinations →
June 22% n=240 All destinations →
July 16% n=248 All destinations →
August 19% n=248 All destinations →
September 36% n=240 All destinations →
October 40% n=248 All destinations →
November 8% n=240 All destinations →
December 3% n=248 All destinations →

Frequently asked

Does it rain in Wilmington in May?

Sometimes. Wilmington sees measurable rain on 40% of days in May historically (n=248 days, ERA5 2018–2025) — not frequent enough to plan around, but not negligible either.

Is Wilmington good for sun in May?

It's mixed. Wilmington in May is clear on 34% of days historically (avg high 80°F, n=248 days, ERA5 2018–2025) — the outcome varies year to year.

How Wilmington compares in May

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against Wilmington this month — same passport tier, similar flight distance, both sides from the same 8-year ERA5 record.

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.