This report describes the typical weather at the Robert L. Bradshaw International Airport (Basseterre, St. Kitts and Nevis) weather station over the course of an average May. It is based on the historical records from 1999 to 2012. Earlier records are either unavailable or unreliable.
Basseterre has a tropical monsoon climate with short dry season. The area within 25 mi of this station is covered by oceans and seas (95%), grasslands (3%), and forests (2%).
The month of May is characterized by essentially constant daily high temperatures, with daily highs around 86°F throughout the month, exceeding 88°F or dropping below 83°F only one day in ten.
Over the course of May, the length of the day is essentially constant. The shortest day of the month is May 1 with 12:46 hours of daylight; the longest day is May 31 with 13:05 hours of daylight.
The earliest sunrise is at 5:36am on May 28; the latest sunset is at 6:42pm on May 31; the latest sunrise is at 5:45am on May 1; the earliest sunset is at 6:31pm on May 1.
Daylight saving time (DST) is not observed in 2012.
The median cloud cover is 66% (partly cloudy) and does not vary substantially over the course of the month.
On May 16, a representative day, the sky is clear or mostly clear 15% of the time, partly cloudy 20% of the time, and mostly cloudy or overcast 30% 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 May, the most common forms of precipitation are light rain, moderate rain, and thunderstorms.
Light rain is the most severe precipitation observed during 62% of those days with precipitation. It is most likely around May 7, when it is observed during 21% of all days.
Moderate rain is the most severe precipitation observed during 25% of those days with precipitation. It is most likely around May 1, when it is observed during 9% of all days.
Thunderstorms are the most severe precipitation observed during 13% of those days with precipitation. They are most likely around May 30, when it is observed during 5% of all days.
Either snow is exceptionally unlikely to fall at this location in May or this station does not reliably report precipitation types.
The relative humidity typically ranges from 65% (mildly humid) to 90% (very humid) over the course of a typical May, rarely dropping below 59% (mildly humid) and reaching as high as 99% (very humid).
The air is driest around May 1, at which time the relative humidity drops below 69% (mildly humid) three days out of four; it is most humid around May 19, rising above 85% (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 May, the dew point typically varies from 71°F (muggy) to 76°F (oppressive) and is rarely below 68°F (muggy) or above 78°F (oppressive).
Over the course of May typical wind speeds vary from 6 mph to 14 mph (light breeze to moderate breeze), rarely exceeding 18 mph (fresh breeze).
The highest average wind speed of 10 mph (gentle breeze) occurs around May 6, at which time the average daily maximum wind speed is 14 mph (moderate breeze).
The lowest average wind speed of 9 mph (gentle breeze) occurs around May 31, at which time the average daily maximum wind speed is 13 mph (moderate breeze).