Methodology

You give each measure an ideal range, a tolerance and an importance. Every city is scored month by month against those preferences, then combined into a single 0–100 score.

• Inside your ideal range scores full marks.
• Outside it, the score falls along a smooth curve measured in units of your tolerance, so nudging a preference never reshuffles your results dramatically.
• Breaking a hard limit sorts a city below every city that passes, however well it scores elsewhere.

Annual averages are never compared. San Francisco and Lisbon have similar annual means and very different climates. Seasons follow each city’s own hemisphere, so your summer preferences meet December–February in Sydney and June–August in Barcelona.

It is not a forecast. These are 1991–2020 averages describing a typical year, not next year.

Neighborhoods differ from cities. A few miles inland from the California coast can mean ten degrees warmer on a summer afternoon.

Counts of extreme days run low. Values are grid estimates, which smooth daily peaks, so days above 90°F and below freezing are conservative — treat them as comparable between cities rather than as a local airport’s figure. This matters most if you set a hard limit on hot days.

Climate is one input among many. Nothing here speaks to cost, safety, jobs, healthcare or visas.

6158 cities across 175 countries, on 1991–2020 climate normals.

Spotted something wrong? Email stormwatchcolin@gmail.com with the city and what you expected.