Climate and monthly weather forecast
Saint Petersburg, Russia

Under the Köppen climate classification system, Saint Petersburg bears a Dfb climate designation, indicating a humid continental climate with no dry season and warm summer. Positioned within Russia's Northwestern Federal District, this city experiences a wide range of weather conditions throughout the year.

Analyzing provided averages of each climatological parameter, it becomes evident that Saint Petersburg weather displays impressive seasonality. Variations include shifting humidity levels between 65% and 87%, monthly high temperatures ranging from -3°C (26.6°F) to 23°C (73.4°F), and low temperatures shifting from a chilly -8.5°C (16.7°F) to a mild 15°C (59°F).

Delving deeper into conditions, the months with the highest rainfall tend to be July, August, and September. Rainfall amounts peak at 79mm (3.11") to 83mm (3.27"), reflecting days with significant rainfall totaling between 17 days to 20 days per month. Snowfall is primarily confined to the colder months, with up to 17 days of snow in January and February, diminishing to no days of snow from May to September.

Meanwhile, the amount of daylight exposure spans from a low of 6.9 hours in December to a light-soaked 18.7 hours in June. This daylight variation strongly influences the duration of sunshine, which varies from a mere 0.4 hours per day in December to a peak of 9.2 hours in June.

Considering the temperature, humidity, rainfall, and daylight parameters together, arguably the most favorable time to visit Saint Petersburg is from May to July. During this period, one can expect high temperatures lying between 16°C (60.8°F) to 23°C (73.4°F), relative humidity ranging from 65% to 71%, and respectable rainfall amounts from 46mm (1.81") to 79mm (3.11") across 16 to 18 rainy days. The city revels in its "White Nights" during this period with long daylight hours peaking at 18.7 hours in June.

In contrast, the least inviting period could potentially be the winter months of December to February. The city experiences the coldest temperatures, with lows reaching -8.5°C (16.7°F) and highs only peaking at -1.5°C (29.3°F). Rainfall also lessens during these months, but the count of snowfall days can reach up to 17 days each month. Coupled with low daylight hours between 6.1 hours and 9.2 hours and minimal sunshine amounts, winter in Saint Petersburg can be quite desolate.

Representing a period of transition, spring in Saint Petersburg spans from March to May. Temperatures gradually warm from lows of -4.2°C (24.4°F) to highs of 16°C (60.8°F). The relative humidity dips to its lowest point of the year at 65%, while the number of rainfall days starts to intensify from 10 up to 16 days across the season. Meanwhile, more intense sunlight begins to permeate the city, with daylight duration extending from 11.8 hours in March to 17.2 hours in May.

Summer, extending from June to August, is distinctly the warmest season. High temperatures range from a mellow 20°C (68°F) in June to a warm 23°C (73.4°F) in July, with lows not descending below 11.7°C (53.1°F). Rain is a common occurrence during this period, with the city experiencing its maximum rainfall days and millimeters of precipitation is accumulated. In Saint Petersburg, during the entire year, the rain falls for 173 days and collects up to 662mm (26.06") of precipitation. January through April, October through December are months with snowfall in Saint Petersburg. The months with the most snowfall days are January, February and December, with an average of 17 snowfall days. In Saint Petersburg, in January, the average water temperature is -0.1°C (31.8°F).
Note: During swimming, this circumstance is both life-threatening and incredibly perilous. The intense cold sensation provokes rapid hyperventilation. The use of a specialized swimsuit is imperative to prevent thermal injuries. In January, the average length of the day is 6h and 53min.
On the first day of the month, sunrise is at 10:00 and sunset at 16:03. On the last day of January, sunrise is at 09:15 and sunset at 17:08 MSK. The average sunshine in January is 0.7h. The months with the lowest UV index are January, November and December, with an average maximum UV index of 0. A UV Index reading of 2, and below, represents a minimal health vulnerability from exposure to the Sun's UV rays for ordinary individuals.
Note: An average UV index of 0 in January transforms into this advice:
Most people can stay in the Sun for up to 1 hour without burning, apart from children that always must be protected from sun exposure. The solar radiation around mid-day is intense; avoid the Sun and stay safe. Wearing a wide-brim hat can block approximately 50% of UV radiation, protecting the eyes. Be advised! The UV radiation from the Sun can be almost doubled due to the reflective properties of snow.

February follows the rhythm of January, maintaining a cold temperature and still witnessing frequent snowfall. The monthly averages reveal that Saint Petersburg continues to endure a low temperature from -8.5°C (16.7°F) to -3°C (26.6°F). Weather in February »

As March settles in, Saint Petersburg starts to hint at the upcoming spring. The temperature sees a slight raise ranging from -4.2°C (24.4°F) to 2°C (35.6°F). Snowfall reduces drastically, and longer daylight hours begin to peek through. Weather in March »

April brings about a transformation in Saint Petersburg's weather, showcasing the first blush of spring. The city experiences a noticeable rise in temperature, measuring from 1.5°C (34.7°F) to 9.3°C (48.7°F). Lush greenery starts to bloom, replacing the winter's stark white scenery. Weather in April »

Come May, spring is in full swing in Saint Petersburg. The increase in temperature is noticeable with longer daylight hours. The city's weather takes a moister turn, yielding an average of 46mm (1.81") of rainfall. The streets are often bustling with life as everyone enjoys the comfortable weather and the charming sights of the awakening cityscape. May's arrival in Saint Petersburg coincides with a rise in the average high-temperature, moving from April's chilly 9.3°C (48.7°F) to a refreshing 16°C (60.8°F). Weather in May »

Random rainfall is a common companion of June, often providing relief from the warm temperatures. The city experiences its highest average rainfall for the year at 71mm (2.8"). Despite the rainfall, Saint Petersburg maintains a welcoming ambiance with long days and blossoming greenery. Weather in June »

July is the peak month of summer in Saint Petersburg with warmth spreading its vibrant hues. With sea temperature reaching up to a comfortable 19°C (66.2°F), it creates a delightful opportunity for waterside activities. Evenings are usually crowded with summer festivals, open-air events and numerous outdoor activities celebrating the city's golden period. July proves to be the warmest month in Saint Petersburg, recording an average peak temperature of 23°C (73.4°F) and a minimum temperature of 15°C (59°F). Weather in July »

Saint Petersburg enters August with lovely sunshine and warm temperatures. Although the sea temperature drops to 18°C (64.4°F), it doesn't affect the bustling life near the water bodies. The city continues to enjoy outdoor activities and cultural fairs, making the most of the remaining summer days. Saint Petersburg's average high-temperature in August is an agreeable 20.8°C (69.4°F), indicating a subtle variation from July. Weather in August »

September brings a gradual change to the weather in Saint Petersburg. Cooler temperatures mark the beginning of autumn with leaves starting to turn colors. The city sees an average rainfall of 64mm (2.52"), adding an extra splash of color to the scenery. Weather in September »

October exhibits splendid autumn colors in Saint Petersburg, paired with a considerable drop in temperature. Darkening evenings with early sunsets become a new normal. Despite the fading warmth, the city maintains its charm with beautiful parks displaying autumn’s vibrant hues and cultural events keeping the city alive. As September transitions to October, the average high-temperature in Saint Petersburg falls from a refreshing 15°C (59°F) to a chilly 8.6°C (47.5°F). Weather in October »

As November arrives, weekend strolls often consist of breathtaking views of the city’s frosty scenery. In this month, the weather takes a colder turn, with snowfall days shooting up to nine days. Despite the chill, Saint Petersburg still possesses a charm that encourages visitors to explore its age-old heritage and stunning architecture. The shift from October to November in Saint Petersburg involves a decrease in the average high-temperature, from a frosty 8.6°C (47.5°F) to a wintry 2°C (35.6°F). Weather in November »

December in Saint Petersburg paints a picture of glistening snow, silver trees under a grey sky, and warm rosy cheeks. The weather is chilly, especially towards the year-end. Longer nights and the festive season create a magical atmosphere with fairy lights and festive decorations spread across the city. Weather in December »