Busan sää — syyskuu

Regulars are consistent that this city runs genuinely warmer than Seoul at the same time of year, though they're quick to add that doesn't mean actually warm - wind can pick up and make a sunny day feel colder than the number suggests. Our row backs that cold, still-mild-for-Korea read, 10.2C over 1.7C nights feeling -2C, with 27.9mm of rain across 3.5 days and a trace of snow, 0.2cm. Regulars are consistent indoor spaces generally have good heating, so the real discomfort comes from walking between destinations rather than time spent inside. A proper padded jacket is the standard packing advice regardless of how mild the forecast looks by Seoul standards. The sea sits at a cold 15.2C. The record: humidity 57 percent, 7.8 hours of sun, an 18 kph wind and AQI 55.

March here is two seasons inside one day - winter in the morning and at night, warm by the afternoon - and Korean has a word for the particular cold snap that arrives near the end of winter, kkotsaemchuwi, the cold that envies the flowers. Our row carries the bite: 14.5C by day but 12C to stand in, 6.4C nights that feel like 3C in a 19 kph wind. On blossom the board is consistent - the trees here open in late March, the Jinhae festival an hour to the west runs from about then into early April, and anyone arriving early in the month is too early. Rain is 86.3mm across 7.6 days, with 1.5cm still in the snow column and a 13.8C sea. The record: humidity 66 percent, 8.8 hours of sun and AQI 76.

June splits around the jangma, the Korean rainy season, which regulars put at roughly mid-June through to some point in July - and they are careful that the dates move and the rainfall is hard to predict. It can come down heavily all day, then break; it can rain one day and be dry the next. Our row reads 163.2mm across 10.5 days, sixteen millimetres apiece, which is that pattern rather than a drizzle. The compensation is the beaches: the peak here is late July into August, so June is the quiet half of the summer, with 25.3C air and a 21.2C sea. The record: 19.4C nights, humidity 83 percent, 9.3 hours of sun and AQI 73.

November in Busan is the gap between the seasons - the autumn leaves are finishing and the snow has not started - and regulars describe the late-autumn south coast as not that cold, warm enough that winter clothes are unnecessary. Our row gives 17.4C days reading as 15C over 8.9C nights. The caveat they add is Korean winter's habit of arriving in bursts: a Siberian air mass can drop a week hard, and one visitor's late-November fortnight ran 8 to 10C by day and below freezing before dawn. So: layers, with something properly warm in the bag for a cold snap that may never come. It is also a dry month here, 43.6mm across 3.7 days. The record: humidity 63 percent, 8.1 hours of sun and a 17.7C sea.