Riga weather in September

Asked whether September brings the golden autumn, regulars answer no - the colour here comes about a month later, mid to late October, and September is the month summer ends rather than the month autumn looks its best. They date the official close of the season to around the 15th. What you get instead is unpredictable: an Indian summer above 25C in some years, wet and grey in others, most often warm and sunny near 20C. Our row averages 18.7C by day but reads as 17C, because the wind is a real 21.4 kph off the Baltic, and nights fall to 8.4C. Rain is 66.9mm across 11.1 days. A jacket and an umbrella whatever the forecast says. The record: humidity 78 percent, 8.6 hours of sun and AQI 37.

Regulars are blunt about real year-to-year swings here - some years bringing a beautiful spring near 20C, others still holding onto the last snow of winter at the same calendar date, with most years landing somewhere around 10-12C. Our row backs that cool, transitional read, 12.4C over 1.2C nights feeling -3C, with 41.4mm of rain across 10 days and a trace of very late snow, 2.7cm, matching regulars' sense that a snow flurry this late isn't impossible. Regulars are specific that outdoor terraces traditionally reopen toward the end of the month, a real marker locals use for when spring has genuinely arrived regardless of what the thermometer says. Layers covering both possibilities remain the standard packing advice. The record: humidity 71 percent, 10.2 hours of sun, a 22.6 kph wind and AQI 49.

Regulars pick May for what is out rather than for the temperature: dandelions, apple and cherry blossom, and most of the wild flora, with the end of the month named as one of the best weeks of the Latvian year. The parks carry it - Bastejkalns, Esplanade, Vermanes, Kronvalda - and even the 1st of May holiday in good weather draws mostly locals rather than crowds. Take their word warm with care: our row gives 18.3C days but 5.3C nights that feel like 2C, so the blossom comes with a coat. Dry is fairer, at 49.9mm across 8.5 days with 12.5 hours of sun inside 16.5 of daylight. The record: humidity 67 percent, a 19.7 kph wind and AQI 48.

August is the warmest month in the Baltics and the one Riga regulars name, with mid-July to mid-August the peak - their range runs 21 to 32C, against our row's 23.2C average high, and summers have gone as high as 35 and as low as 15. The useful detail is when the rain falls: they describe August rain as mostly overnight, with daytime showers light and short, and even the thundery spells that follow a hot dry run tending to arrive at night. Our row's 94.9mm across 14.2 precipitation days is a lot of days for a month described as fine, and that timing is the reconciliation. A light jacket becomes necessary from September. The record: 11.7C nights, 10.9 hours of sun and a 20.4C sea.

July is the warmest month on the Riga forum's own account, with the caveat locals keep adding: in recent years it has been less dependable, and a July week can still come out wet and chilly. The standing planning rule posters give is not to push a summer trip past about 10 to 15 August, when the odds of low temperatures or rain, or both, climb sharply. Jurmala is half an hour out by train and the swing is the same - sun and warmth make the dunes, beaches and cafes worth the whole day, while rain and anything under 20C leaves little to do. Sea reports run from around 22C to far too cold. The record: 23.7C days, 12.8C nights, 13.4 precipitation days and 95.7mm, 12.5 hours of sun in a 17-hour day, a 19.9C sea, AQI 38.