ERA5 almanac — 8 years of real data

Scottsdale Desert Ridge in September

Scottsdale Desert Ridge in September: 10% of days see measurable rain, 98°F average high, 82% of days historically clear (n=240, ERA5 2018–2025).

Historically one of the better months to visit Scottsdale Desert Ridge for sun: 82% of days are clear on average (n=240, avg high 98°F). Every percentage here is a historical average from 8 years of ERA5 data — 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 Scottsdale Desert Ridge 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 Scottsdale Desert Ridge 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	82%	n=120	98°F
Late September 16th–end	82%	n=120	98°F
Full month average	82%	n=240	98°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 Scottsdale Desert Ridge 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	100%	n=120
Late September 16th–end	98%	n=120
Full month average	99%	n=240

11.8 h median sunshine per day 96% of days exceed 8 h sunshine 10% of days see ≥ 1 mm rain — rain is not hidden

Comparison (old vs new): WMO-code “clear” bar: 82%. Sunshine-based “warm & sunny”: 99%. The 17-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

Scottsdale Desert Ridge is historically one of the best destinations for sun in September: 82% of days meet the clear bar (avg high 98°F, n=240 days across 8 years). Pack for outdoor activity — this month consistently delivers.

Every month in Scottsdale Desert Ridge

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

Historical clear-sky % for Scottsdale Desert Ridge, all months, ERA5 2018–2025.
Month	% Clear	Sample (n)
January	13%	n=248	All destinations →
February	35%	n=226	All destinations →
March	46%	n=248	All destinations →
April	92%	n=240	All destinations →
May	92%	n=248	All destinations →
June	94%	n=240	All destinations →
July	76%	n=248	All destinations →
August	78%	n=248	All destinations →
September ← this page	82%	n=240	All destinations →
October	85%	n=248	All destinations →
November	58%	n=240	All destinations →
December	18%	n=248	All destinations →

Frequently asked

Does it rain in Scottsdale Desert Ridge in September?

Rarely. Only 10% of days in Scottsdale Desert Ridge see measurable rain in September, based on 8 years of ERA5 historical data (n=240 days, 2018–2025). This is a historical average, not a forecast.

Is Scottsdale Desert Ridge good for sun in September?

Yes. Scottsdale Desert Ridge is historically strong for sun in September: 82% of days are clear on average (avg high 98°F, n=240 days, ERA5 2018–2025).

How Scottsdale Desert Ridge compares in September

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

→ Scottsdale Desert Ridge vs Phoenix in September — Phoenix is 82% clear historically
→ Scottsdale Desert Ridge vs Scottsdale in September — Scottsdale is 82% clear historically
→ Scottsdale Desert Ridge vs Laguna Beach in September — Laguna Beach is 83% clear historically

→ Scottsdale Desert Ridge 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.