This report describes the typical weather at the Cyril E. King Airport (St. Thomas, US Virgin Islands) 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.
St. Thomas has a tropical savanna climate with dry winters. The area within 25 mi of this station is covered by oceans and seas (99%).
The month of March is characterized by essentially constant daily high temperatures, with daily highs around 84°F throughout the month, exceeding 89°F or dropping below 81°F only one day in ten.
Over the course of March, the length of the day is gradually increasing. The shortest day of the month is March 1 with 11:48 hours of daylight; the longest day is March 31 with 12:19 hours of daylight.
The earliest sunrise is at 6:15am on March 31; the latest sunset is at 6:34pm on March 31; the latest sunrise is at 6:39am on March 1; the earliest sunset is at 6:26pm on March 2.
Daylight savings time (DST) is not observed in 2012.
The median cloud cover is 22% (mostly clear) and does not vary substantially over the course of the month.
On March 16, a representative day, the sky is clear or mostly clear 52% of the time, partly cloudy 6% of the time, and mostly cloudy or overcast 18% of the time.
The average probability that some form of precipitation will be observed in a given day is 23%, with little variation over the course of the month.
Throughout March, the most common forms of precipitation are light rain, moderate rain, and heavy rain.
Light rain is the most severe precipitation observed during 54% of those days with precipitation. It is most likely around March 1, when it is observed during 14% of all days.
Moderate rain is the most severe precipitation observed during 27% of those days with precipitation. It is most likely around March 15, when it is observed during 7% of all days.
Heavy rain is the most severe precipitation observed during 18% of those days with precipitation. It is most likely around March 29, when it is observed during 5% of all days.
Either snow is exceptionally unlikely to fall at this location in March or this station does not reliably report precipitation types.
The relative humidity typically ranges from 56% (mildly humid) to 82% (humid) over the course of a typical March, rarely dropping below 45% (comfortable), or exceeding 92% (very humid).
The air is driest around March 2, at which time the relative humidity drops below 60% (mildly humid) three days out of four; it is most humid around March 31, 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 64°F (mildy humid) to 70°F (muggy) and is rarely below 58°F (comfortable) or above 74°F (very muggy).
Over the course of March typical wind speeds vary from 6 mph to 17 mph (light breeze to moderate breeze), rarely exceeding 22 mph (fresh breeze).
The highest average wind speed of 11 mph (gentle breeze) occurs around March 1, 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 24, at which time the average daily maximum wind speed is 17 mph (moderate breeze).