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SunnyDays

ERA5 almanac — 8 years of real data

30A / Seaside in June

30A / Seaside in June: 62% of days see measurable rain, 86°F average high, 16% of days historically clear (n=240, ERA5 2018–2025).

30A / Seaside in June is historically a poor month for sun: only 16% of days clear across 8 years (n=240, avg high 86°F). October is the clearest month for 30A / Seaside historically. 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 30A / Seaside 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 June

Clear-sky percentage for 30A / Seaside in June, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early June
1st–15th		 16% n=120 86°F
Late June
16th–end		 16% n=120 86°F
Full month average 16% n=240 86°F

Sunshine & warmth in June

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 30A / Seaside in June. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early June
1st–15th		 96% n=120
Late June
16th–end		 96% n=120
Full month average 96% n=240
13.0 h median sunshine per day 90% of days exceed 8 h sunshine 62% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 16%. Sunshine-based “warm & sunny”: 96%. The 80-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

30A / Seaside is a poor choice for sun in June: just 16% of days clear historically (n=240). October is the historically strongest month for sun here. The 8-year record is consistent — this is not a fluke bad stretch.

→ See all destinations in October — historically the best month for sun in 30A / Seaside.

Every month in 30A / Seaside

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

Historical clear-sky % for 30A / Seaside, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 1% n=248 All destinations →
February 5% n=226 All destinations →
March 12% n=248 All destinations →
April 41% n=240 All destinations →
May 42% n=248 All destinations →
June ← this page 16% n=240 All destinations →
July 9% n=248 All destinations →
August 12% n=248 All destinations →
September 32% n=240 All destinations →
October 51% n=248 All destinations →
November 24% n=240 All destinations →
December 4% n=248 All destinations →

Frequently asked

Does it rain in 30A / Seaside in June?

Yes, frequently. In 30A / Seaside, 62% of days in June see measurable rain, based on 8 years of ERA5 historical data (n=240 days, 2018–2025). This is a historical average, not a forecast.

Is 30A / Seaside good for sun in June?

Not usually. 30A / Seaside is historically overcast in June: only 16% of days are clear (avg high 86°F, n=240 days, ERA5 2018–2025). October is historically far better for sun here.

How 30A / Seaside compares in June

Head-to-head clear-sky comparisons against destinations travelers plausibly weigh against 30A / Seaside 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.