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SunnyDays

ERA5 almanac — 8 years of real data

Cartagena in October

Cartagena in October: 84% of days see measurable rain, 85°F average high, 1% of days historically clear (n=248, ERA5 2018–2025).

Cartagena in October is historically a poor month for sun: only 1% of days clear across 8 years (n=248, avg high 85°F). February is the clearest month for Cartagena 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 Cartagena 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 October

Clear-sky percentage for Cartagena in October, split by half-month. “n” is the number of days sampled across 8 years (2018–2025).
Period % Clear days Sample (n) Avg high
Early October
1st–15th		 0% n=120 85°F
Late October
16th–end		 2% n=128 85°F
Full month average 1% n=248 85°F

Sunshine & warmth in October

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 Cartagena in October. Primary: % of days ≥ 72°F with > 6 h of sunshine.
Period Warm & sunny (≥72°F, >6 h sun) Sample (n)
Early October
1st–15th		 83% n=120
Late October
16th–end		 92% n=128
Full month average 88% n=248
9.8 h median sunshine per day 73% of days exceed 8 h sunshine 84% of days see ≥ 1 mm rain — rain is not hidden
Comparison (old vs new): WMO-code “clear” bar: 1%. Sunshine-based “warm & sunny”: 88%. The 87-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

Cartagena is historically almost never clear in October: only 1% of days meet the clear bar across 8 years (n=248). Come back in February if you want clear skies here. Plan entirely around indoor or overcast-friendly activities.

→ See all destinations in February — historically the best month for sun in Cartagena.

Every month in Cartagena

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

Historical clear-sky % for Cartagena, all months, ERA5 2018–2025.
Month % Clear Sample (n)
January 51% n=248 All destinations →
February 56% n=226 All destinations →
March 35% n=248 All destinations →
April 10% n=240 All destinations →
May 5% n=248 All destinations →
June 4% n=240 All destinations →
July 4% n=248 All destinations →
August 3% n=248 All destinations →
September 1% n=240 All destinations →
October ← this page 1% n=248 All destinations →
November 4% n=240 All destinations →
December 26% n=248 All destinations →

Frequently asked

Does it rain in Cartagena in October?

Yes, frequently. In Cartagena, 84% of days in October see measurable rain, based on 8 years of ERA5 historical data (n=248 days, 2018–2025). This is a historical average, not a forecast.

Is Cartagena good for sun in October?

Not usually. Cartagena is historically overcast in October: only 1% of days are clear (avg high 85°F, n=248 days, ERA5 2018–2025). February is historically far better for sun here.

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.