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SunnyDays

ERA5 almanac comparison — 8 years of real data

Outer Banks vs Tucson: weather in September

Tucson is the clear winner for sun in September: 70% of days historically clear versus just 40% in Outer Banks — a 30-point gap across 8 years of ERA5 data. Outer Banks also sees measurably more rain than Tucson this month (36% vs 20% of days). This isn't close.

What you are reading: 8-year historical averages, not a forecast. Either destination can still surprise you this specific September. For this week’s actual forecast, each destination links to its live page below.

Outer Banks

NC

Clear days, September
40%
Sample size
n=240 days
Avg high
78°F
Early September (1st–15th)
38%
Late September (16th–end)
43%
Rain frequency
36% of days

Tucson

AZ

Clear days, September
70%
Sample size
n=240 days
Avg high
96°F
Early September (1st–15th)
72%
Late September (16th–end)
69%
Rain frequency
20% of days

Compare Outer Banks vs Tucson in another month

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.