ERA5 almanac — 8 years of real data

30A / Seaside in March

30A / Seaside in March: rain frequency data not yet backfilled for this month, 70°F average high, 12% of days historically clear (n=248, ERA5 2018–2025).

30A / Seaside in March is historically a poor month for sun: only 12% of days clear across 8 years (n=248, avg high 70°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 March

Clear-sky percentage for 30A / Seaside in March, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period	% Clear days	Sample (n)	Avg high
Early March 1st–15th	11%	n=120	70°F
Late March 16th–end	12%	n=128	70°F
Full month average	12%	n=248	70°F

Bottom line

30A / Seaside is a poor choice for sun in March: just 12% of days clear historically (n=248). 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 ← this page	12%	n=248	All destinations →
April	41%	n=240	All destinations →
May	42%	n=248	All destinations →
June	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

Is 30A / Seaside good for sun in March?

Not usually. 30A / Seaside is historically overcast in March: only 12% of days are clear (avg high 70°F, n=248 days, ERA5 2018–2025). October is historically far better for sun here.

→ 30A / Seaside live forecast — this week’s actual 7-day weather, not historical
→ Best destinations in March — all destinations ranked by March clear-sky %
→ All destinations
→ Raw data (JSON) — buckets, n, source

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.