Saint Petersburg sits in the far northwest of Russia at the head of the Gulf of Finland, on the low, flat delta of the Neva River, at approximately 59.94°N, 30.31°E — one of the most northerly major cities in the world. Its coastal, Baltic position gives it a humid continental climate (Köppen Dfb) that is milder, cloudier and damper than inland Moscow, with cold, snowy winters, cool summers and famously changeable, overcast weather.

Summer, from June to August, is short, cool and mild, with July the warmest month — average highs around 22–23°C and cool nights — kept gentler than inland Russia by the Baltic. The far-northern latitude brings the celebrated 'white nights' around midsummer, when the sun barely sets and twilight lingers through the night. It is among the wetter, cloudier seasons, with frequent showers, but the long luminous days make it the liveliest time of year.

Winter, from November to March, is long, cold, dark and damp, though milder than Moscow thanks to the sea, with January and February the coldest — average highs around -3 to -5°C and lows near -8°C, with colder snaps below -20°C. Snow lies for months and the Neva and gulf can freeze. Midwinter days are strikingly short, with only around six hours of murky daylight, and grey, sunless skies dominate.

Saint Petersburg receives around 700–730 mm of precipitation a year, spread through every month with a late-summer and autumn maximum; it is one of the cloudiest and dampest of Russia's big cities, with frequent light rain and drizzle. A large share of the winter total falls as snow. Live rainfall, humidity, and pressure readings for the city are shown in the panels above.

Two features set Saint Petersburg apart: the extreme swing in daylight — from the barely-dark 'white nights' of June to the six-hour days of December — and its low, delta setting, which has historically made it prone to devastating floods when Baltic storms drive water up the Gulf of Finland into the Neva, a threat now held back by a vast flood barrier. Its Baltic position keeps it milder but greyer and damper than the Russian interior.

To follow any single measurement in Saint Petersburg more closely, use our live instruments: the online barometer for atmospheric pressure, the thermometer for temperature, the hygrometer for humidity, the anemometer for wind speed, the wind vane for wind direction, and the rain gauge for rainfall.