This report describes the typical weather at the Jacksonville International Airport (Jacksonville, Florida, United States) weather station over the course of an average April. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Jacksonville, Florida has a warm humid temperate climate with hot summers and no dry season. The area within 25 mi of this station is covered by forests (50%), croplands (24%), oceans and seas (11%), built-up areas (7%), and lakes and rivers (5%).
The month of April is characterized by rising daily high temperatures, with daily highs increasing from 76°F to 82°F over the course of the month, exceeding 89°F or dropping below 67°F only one day in ten.
Over the course of April, the length of the day is gradually increasing. From the start to the end of the month, the length of the day increases by 50 minutes, implying an average day-over-day increase of 1.7 minutes.
The shortest day of the month is April 1 with 12:31 hours of daylight; the longest day is April 30 with 13:21 hours of daylight.
The earliest sunrise is at 6:44am on April 30; the latest sunset is at 8:05pm on April 30; the latest sunrise is at 7:15am on April 1; the earliest sunset is at 7:46pm on April 1.
Daylight saving time is observed in 2012 but it neither starts nor ends in April, so the entire month is in daylight time.
The median cloud cover is 46% (partly cloudy) and does not vary substantially over the course of the month.
On April 15, a representative day, the sky is clear or mostly clear 46% of the time, partly cloudy 19% of the time, and mostly cloudy or overcast 33% of the time.
The average probability that some form of precipitation will be observed in a given day is 32%, with little variation over the course of the month.
Throughout April, the most common forms of precipitation are thunderstorms, moderate rain, and light rain.
Thunderstorms are the most severe precipitation observed during 36% of those days with precipitation. They are most likely around April 29, when it is observed during 14% of all days.
Moderate rain is the most severe precipitation observed during 34% of those days with precipitation. It is most likely around April 1, when it is observed during 12% of all days.
Light rain is the most severe precipitation observed during 25% of those days with precipitation. It is most likely around April 1, when it is observed during 9% of all days.
Either snow is exceptionally unlikely to fall at this location in April or this station does not reliably report precipitation types.
The relative humidity typically ranges from 43% (comfortable) to 95% (very humid) over the course of a typical April, rarely dropping below 26% (dry) and reaching as high as 100% (very humid).
The air is driest around April 12, at which time the relative humidity drops below 52% (mildly humid) three days out of four; it is most humid around April 30, rising above 93% (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 48°F (dry) to 65°F (mildy humid) and is rarely below 34°F (dry) or above 71°F (very muggy).
The time of the month between April 1 and April 30 is the most comfortable, with dew points that are neither too dry nor too muggy.
Over the course of April typical wind speeds vary from 0 mph to 16 mph (calm to moderate breeze), rarely exceeding 21 mph (fresh breeze).
The highest average wind speed of 8 mph (gentle breeze) occurs around April 6, at which time the average daily maximum wind speed is 15 mph (moderate breeze).
The lowest average wind speed of 7 mph (light breeze) occurs around April 27, at which time the average daily maximum wind speed is 15 mph (moderate breeze).