Tokyo weather in September

September looks decent and is a gamble: the first half is still summer humidity, and typhoon season peaks now. I've had a perfect week and I've had two days indoors watching trains cancel. Late September is safer than early.

Tokyo-forum threads asking if August really is that hot get a consistent yes, posters comparing the combination of heat and humidity to Houston or Dallas at their peak, occasionally worse. A long, steady multi-day soak is called rare unless a typhoon happens to track nearby - the more typical pattern is a sudden, heavy afternoon squall once the air turns oppressively muggy, clearing within an hour or so. The Obon holiday falls mid-month, when many businesses close and inter-city trains get noticeably more crowded. Regulars recommend planning around the worst midday heat - museums, department stores and shaded shrine grounds over long outdoor stretches - and treating frequent convenience-store stops for cold drinks as a genuine survival strategy. The record: 32.1C days feeling like a punishing 37C, 24.6C nights, 116mm across 11.6 days, an 28.8C sea, 80 percent humidity and 9.9 hours of sun.

Tokyo-forum threads on February weather describe a month that's genuinely cold but reliably clear - sunny, dry, 'brisk' days rather than the grey damp of a European winter. The packing advice is thorough: a proper coat, thermal base layers, gloves and a scarf for outside, but posters are equally insistent that trains and indoor spaces run heated to the point of overheating, so the layers need to come off easily rather than staying zipped up all day. The payoff for the cold is lower crowds than any other season. The record: 11.6C days feeling like 8C, 2C nights, 48mm of rain across 7.1 days, 3.8cm of snowfall and 8.4 hours of sun - genuinely cold, with enough rain and a little snow mixed through the month's clear stretches.

Tokyo-forum threads on Golden Week (the run of holidays through early May) make a distinction worth knowing: Tokyoites leave the city for the break, so ordinary neighbourhoods and trains actually get quieter even as sightseeing spots and shopping districts fill with domestic travellers. Regulars steer visitors toward the second half of the month instead, once the holiday clears, for the same pleasant weather with thinner crowds. May's record: 24.1C days, 14.9C nights, 128mm of rain across nearly twelve days, 8.7 hours of sun and an AQI of 75 - warm and humid enough to read as early summer, not spring.

Forum posters consistently rate October as one of the best months to visit Japan, with average Tokyo temperatures around 17C - not too hot, not too cold. Posters describe early October as sometimes still a bit warm, cooling further as the month progresses, with short sleeves comfortable by day and a jacket or sweater needed once temperatures drop at night. Posters generally describe October and November as reliably dry with great weather, though they flag a real caveat: lingering typhoon risk means rainfall totals can vary a lot from year to year even in this generally favorable stretch. Posters consistently note October isn't Tokyo's busiest tourist season, a real bonus alongside the comfortable weather.