This report describes the typical weather at the Pulkovo Airport (Saint Petersburg, Russian Federation) weather station over the course of an average April. It is based on the historical records from 2006 to 2012. Earlier records are either unavailable or unreliable.
Saint Petersburg has a humid continental climate with warm summers and no dry season. The area within 25 mi of this station is covered by forests (54%), croplands (21%), oceans and seas (14%), and built-up areas (8%).
The month of April is characterized by rapidly rising daily high temperatures, with daily highs increasing from 42°F to 56°F over the course of the month, exceeding 65°F or dropping below 36°F only one day in ten.
Over the course of April, the length of the day is very rapidly increasing. From the start to the end of the month, the length of the day increases by 2:35 hours, implying an average day-over-day increase of 5.2 minutes.
The shortest day of the month is April 1 with 13:20 hours of daylight; the longest day is April 30 with 15:55 hours of daylight.
The earliest sunrise is at 5:59am on April 30; the latest sunset is at 9:54pm on April 30; the latest sunrise is at 7:23am on April 1; the earliest sunset is at 8:43pm on April 1.
Daylight savings time (DST) is not observed in 2012.
The median cloud cover is 96% (overcast) and does not vary substantially over the course of the month.
On April 15, a representative day, the sky is clear or mostly clear 2% of the time, partly cloudy 4% of the time, and mostly cloudy or overcast 46% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around April 1, occurring in 54% of days. Precipitation is least likely around April 22, occurring in 49% of days.
Throughout April, the most common forms of precipitation are light rain, moderate snow, and light snow.
Light rain is the most severe precipitation observed during 59% of those days with precipitation. It is most likely around April 30, when it is observed during 37% of all days.
Moderate snow is the most severe precipitation observed during 22% of those days with precipitation. It is most likely around April 1, when it is observed during 16% of all days.
Light snow is the most severe precipitation observed during 12% of those days with precipitation. It is most likely around April 1, when it is observed during 12% of all days.
The likelihood of snow falling is highest around April 1, occurring in 30% of days.
Either snow rarely accumulates at this location in April or snow depth measurements are unavailable or unreliable.
The relative humidity typically ranges from 40% (comfortable) to 93% (very humid) over the course of a typical April, rarely dropping below 25% (dry) and reaching as high as 99% (very humid).
The air is driest around April 30, at which time the relative humidity drops below 47% (comfortable) three days out of four; it is most humid around April 1, rising above 90% (very humid) three days out of four.
Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.
Over the course of a typical April, the dew point typically varies from 23°F (dry) to 39°F (dry) and is rarely below 14°F (dry) or above 46°F (dry).
Over the course of April typical wind speeds vary from 1 mph to 9 mph (light air to gentle breeze), rarely exceeding 17 mph (moderate breeze).
The highest average wind speed of 6 mph (light breeze) occurs around April 27, at which time the average daily maximum wind speed is 9 mph (gentle breeze).
The lowest average wind speed of 5 mph (light breeze) occurs around April 6, at which time the average daily maximum wind speed is 8 mph (gentle breeze).