Where to go in September

132 cities, one measured yardstick: average highs, rain days, rain hours and daylight from multi-year Open-Meteo records. 38 cities sit in the ideal band this month. Ranked by disclosed thresholds the skip list included.

September splits cleanly across TTDI's 87 measured cities. 29 land in the ideal comfort band, the single largest group. Another 21 sit in good territory, and together those bands cover more than half the measured set. The lower end divides between 18 mixed and 19 difficult, a near-even pair. September tips toward comfort on balance, but 19 cities in the difficult band is a real share of the 87.

Mykonos leads the ranked list with an average high of 26°C and 1 rain day. San Francisco follows at 20°C and 1 rain day. Cappadocia matches Mykonos at 26°C but records 2 rain days. Athens, Bucharest, Beijing, Edmonton, and Crete complete the featured eight. The top three share dry conditions. None of them recorded more than 2 rain days in September.

19 of the 87 measured cities land in the difficult band, 1 more than the 18 in mixed. September's data leans favorable, but the difficult band tracks close behind the 21 in good.

Mykonos leads September's ranking with an average high of 26°C and 1 rain day.

Nº 1

Lima

Ideal in September

  • 19° / 14° high / low
  • 0.0 h rain/day
  • 12.1 h daylight

19° highs with 0 rain days: inside the ideal window (18–29 °C highs, ≤13 rain days, ≤90 mm).

Things to do in Lima in September →

Nº 31

Riga

Ideal in September

  • 18° / 11° high / low
  • 1.0 h rain/day
  • 12.7 h daylight

18° highs with 10 rain days: inside the ideal window (18–29 °C highs, ≤13 rain days, ≤90 mm).

Things to do in Riga in September →

Nº 32

Paris

Ideal in September

  • 22° / 13° high / low
  • 1.5 h rain/day
  • 12.5 h daylight

22° highs with 11 rain days: inside the ideal window (18–29 °C highs, ≤13 rain days, ≤90 mm).

Things to do in Paris in September →

Measurably difficult in September

Honesty cuts both ways: these cities trip a difficult threshold this month:

  • Abu Dhabi : 39° highs clear the 37 °C heat threshold: measurably difficult.
  • Dubai : 39° highs clear the 37 °C heat threshold: measurably difficult.
  • Doha : 39° highs clear the 37 °C heat threshold: measurably difficult.
  • Phoenix : 38° highs clear the 37 °C heat threshold: measurably difficult.
  • Seoul : 215 mm of rain clears the 200 mm threshold: measurably difficult.
  • Tokyo : 202 mm of rain clears the 200 mm threshold: measurably difficult.
  • Taipei : 206 mm of rain clears the 200 mm threshold: measurably difficult.
  • St. Augustine : 201 mm of rain clears the 200 mm threshold: measurably difficult.
  • San Juan : Rain on 20 days clears the 20-day threshold: measurably difficult.
  • Cancun : Rain on 20 days clears the 20-day threshold: measurably difficult.
  • Guangzhou : Rain on 20 days clears the 20-day threshold: measurably difficult.
  • Medellin : Rain on 21 days clears the 20-day threshold: measurably difficult.
  • Ubud : Rain on 22 days clears the 20-day threshold: measurably difficult.
  • Montego Bay : Rain on 22 days clears the 20-day threshold: measurably difficult.
  • Orlando : Rain on 23 days clears the 20-day threshold: measurably difficult.
  • Cartagena : Rain on 23 days clears the 20-day threshold: measurably difficult.
  • Puerto Vallarta : Rain on 23 days clears the 20-day threshold: measurably difficult.
  • Varanasi : Rain on 23 days clears the 20-day threshold: measurably difficult.
  • Fort Lauderdale : Rain on 24 days clears the 20-day threshold: measurably difficult.
  • Miami : Rain on 24 days clears the 20-day threshold: measurably difficult.
  • Pattaya : Rain on 25 days clears the 20-day threshold: measurably difficult.
  • Singapore : Rain on 25 days clears the 20-day threshold: measurably difficult.
  • Boracay : Rain on 26 days clears the 20-day threshold: measurably difficult.
  • Goa : Rain on 27 days clears the 20-day threshold: measurably difficult.
  • Cebu : Rain on 27 days clears the 20-day threshold: measurably difficult.
  • Mumbai : Rain on 28 days clears the 20-day threshold: measurably difficult.
  • Kauai : Rain on 28 days clears the 20-day threshold: measurably difficult.
  • Bangkok : Rain on 28 days clears the 20-day threshold: measurably difficult.
  • San José : Rain on 29 days clears the 20-day threshold: measurably difficult.
  • Kathmandu : Rain on 29 days clears the 20-day threshold: measurably difficult.

Tracked events in September

  • 18 Sept 2026 CROISIÈRE DÉJEUNER - 12H45 BATEAUX PARISIENS, Paris
  • 18 Sept 2026 Twist Museum - London's Home of Illusions STANDARD Twist Museum, London
  • 18 Sept 2026 Twist Museum - London's Home of Illusions STANDARD Twist Museum, London
  • 18 Sept 2026 ANDY WARHOL - ENTRÉE SIMPLE MUSEE DU LUXEMBOURG, Paris
  • 18 Sept 2026 Museo Banksy Madrid Museo Banksy Madrid, Madrid
  • 18 Sept 2026 Franck (All Night Long) Liberty Hall, Sydney
  • 18 Sept 2026 AQUARIUM DE PARIS - AQUARIUM DE PARIS - BASSE SAISON AQUARIUM DE PARIS, Paris
  • 18 Sept 2026 Ramses and the Pharaoh’s Gold: The Exhibition Neon at Battersea Power Station, London
  • 18 Sept 2026 Museo Banksy Barcelona Barcelona
  • 18 Sept 2026 Chinese Laundry Invites FRICTION [FULL VENUE TAKEOVER] & KID KENOBI [30 YEARS] Chinese Laundry, Sydney

From the live events feed we sync daily: listings exist only where measured coverage does.

September, answered from the data

Where is it ideal to travel in September?

38 of the 132 cities we measure sit in the ideal band in September; Lima, Mykonos, San Francisco lead the ranking.

Which city is coolest in September?

Reykjavik, with average highs of 10 °C in our measured record.

Which city is driest in September?

Lima, averaging 0 rain days across the month.

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