ERA5 almanac — 8 years of real data

Turks & Caicos in September

Turks & Caicos in September: 50% of days see measurable rain, 85°F average high, 16% of days historically clear (n=240, ERA5 2018–2025).

Turks & Caicos in September is historically a poor month for sun: only 16% of days clear across 8 years (n=240, avg high 85°F). March is the clearest month for Turks & Caicos 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 Turks & Caicos 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 September

Clear-sky percentage for Turks & Caicos in September, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period	% Clear days	Sample (n)	Avg high
Early September 1st–15th	19%	n=120	85°F
Late September 16th–end	13%	n=120	85°F
Full month average	16%	n=240	85°F

Sunshine & warmth in September

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 Turks & Caicos in September. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period	Warm & sunny (≥72°F, >6 h sun)	Sample (n)
Early September 1st–15th	98%	n=120
Late September 16th–end	98%	n=120
Full month average	98%	n=240

11.7 h median sunshine per day 98% of days exceed 8 h sunshine 50% of days see ≥ 1 mm rain — rain is not hidden

Comparison (old vs new): WMO-code “clear” bar: 16%. Sunshine-based “warm & sunny”: 98%. The 82-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

Turks & Caicos is a poor choice for sun in September: just 16% of days clear historically (n=240). March 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 March — historically the best month for sun in Turks & Caicos.

Every month in Turks & Caicos

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

Historical clear-sky % for Turks & Caicos, all months, ERA5 2018–2025.
Month	% Clear	Sample (n)
January	34%	n=248	All destinations →
February	36%	n=226	All destinations →
March	40%	n=248	All destinations →
April	38%	n=240	All destinations →
May	23%	n=248	All destinations →
June	28%	n=240	All destinations →
July	23%	n=248	All destinations →
August	27%	n=248	All destinations →
September ← this page	16%	n=240	All destinations →
October	16%	n=248	All destinations →
November	24%	n=240	All destinations →
December	27%	n=248	All destinations →

Frequently asked

Does it rain in Turks & Caicos in September?

Yes, frequently. In Turks & Caicos, 50% of days in September 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 Turks & Caicos good for sun in September?

Not usually. Turks & Caicos is historically overcast in September: only 16% of days are clear (avg high 85°F, n=240 days, ERA5 2018–2025). March is historically far better for sun here.

How Turks & Caicos compares in September

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

→ Turks & Caicos vs Bar Harbor in September — Bar Harbor is 16% clear historically
→ Turks & Caicos vs St. Augustine in September — St. Augustine is 17% clear historically
→ Turks & Caicos vs St. John, USVI in September — St. John, USVI is 15% clear historically

→ Turks & Caicos live forecast — this week’s actual 7-day weather, not historical
→ Best destinations in September — all destinations ranked by September 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.