This report describes the typical weather at the Pittsburgh International Airport (Pittsburgh, Pennsylvania, United States) weather station over the course of an average March. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Pittsburgh, Pennsylvania has a humid continental climate with hot summers and no dry season. The area within 25 mi of this station is covered by forests (78%) and built-up areas (19%).
The month of March is characterized by rapidly rising daily high temperatures, with daily highs increasing from 44°F to 55°F over the course of the month, exceeding 72°F or dropping below 29°F only one day in ten.
Over the course of March, the length of the day is increasing. From the start to the end of the month, the length of the day increases by 1:21 hours, implying an average day-over-day increase of 2.6 minutes.
The shortest day of the month is March 1 with 11:19 hours of daylight; the longest day is March 31 with 12:40 hours of daylight.
The earliest sunrise is at 6:40am on March 10; the latest sunset is at 7:45pm on March 31; the latest sunrise is at 7:38am on March 11; the earliest sunset is at 6:13pm on March 1.
Daylight savings time (DST) starts at 3:00am on March 11, 2012, shifting sunrise and sunset to an hour later.
The median cloud cover ranges from 89% (mostly cloudy) to 95% (mostly cloudy). The trend is for the sky to be clearing with the median cloud cover decreasing by 5% from the start to the end of the month.
On March 16, a representative day, the sky is clear or mostly clear 22% of the time, partly cloudy 14% of the time, and mostly cloudy or overcast 63% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around March 1, occurring in 68% of days. Precipitation is least likely around March 31, occurring in 60% of days.
Throughout March, the most common forms of precipitation are light snow, light rain, moderate rain, and moderate snow.
Light snow is the most severe precipitation observed during 38% of those days with precipitation. It is most likely around March 1, when it is observed during 31% of all days.
Light rain is the most severe precipitation observed during 22% of those days with precipitation. It is most likely around March 31, when it is observed during 17% of all days.
Moderate rain is the most severe precipitation observed during 14% of those days with precipitation. It is most likely around March 31, when it is observed during 11% of all days.
Moderate snow is the most severe precipitation observed during 12% of those days with precipitation. It is most likely around March 1, when it is observed during 10% of all days.
The likelihood of snow falling is highest around March 1, occurring in 44% of days.
Accumulation at this location in March is unlikely. The chances of there being snow on the ground are highest around March 1, occurring 31% of the time.
The snow is typically at its deepest on March 1, with a median depth of 2.5"; the depth exceeds 7.3" only one year out of ten.
The relative humidity typically ranges from 42% (comfortable) to 84% (humid) over the course of a typical March, rarely dropping below 23% (dry) and reaching as high as 99% (very humid).
The air is driest around March 31, at which time the relative humidity drops below 51% (mildly humid) three days out of four; it is most humid around March 1, rising above 77% (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 March, the dew point typically varies from 17°F (dry) to 38°F (dry) and is rarely below 5°F (dry) or above 53°F (very comfortable).
Over the course of March typical wind speeds vary from 3 mph to 17 mph (light air to moderate breeze), rarely exceeding 25 mph (strong breeze).
The highest average wind speed of 10 mph (gentle breeze) occurs around March 30, at which time the average daily maximum wind speed is 17 mph (moderate breeze).
The lowest average wind speed of 10 mph (gentle breeze) occurs around March 1, at which time the average daily maximum wind speed is 16 mph (moderate breeze).