This report describes the typical weather at the George F. L. Charles Airport (Vigie Airport) (Castries, St. Lucia) weather station over the course of an average December. It is based on the historical records from 2008 to 2012. Earlier records are either unavailable or unreliable.
Castries has a tropical savanna climate with dry winters. The area within 25 mi of this station is covered by oceans and seas (88%), grasslands (10%), and croplands (3%).
The month of December is characterized by essentially constant daily high temperatures, with daily highs around 84°F throughout the month, exceeding 86°F or dropping below 82°F only one day in ten.
Over the course of December, the length of the day is essentially constant. The shortest day of the month is December 28 with 11:18 hours of daylight; the longest day is December 4 with 11:21 hours of daylight.
The earliest sunrise is at 6:13am on December 1; the latest sunset is at 5:47pm on December 31; the latest sunrise is at 6:28am on December 30; the earliest sunset is at 5:34pm on December 1.
Daylight saving time (DST) is not observed in 2012.
The median cloud cover is 56% (partly cloudy) and does not vary substantially over the course of the month.
On December 16, a representative day, the sky is clear or mostly clear 17% of the time, partly cloudy 19% of the time, and mostly cloudy or overcast 28% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around December 2, occurring in 44% of days. Precipitation is least likely around December 10, occurring in 40% of days.
Throughout December, the most common forms of precipitation are light rain and moderate rain.
Light rain is the most severe precipitation observed during 55% of those days with precipitation. It is most likely around December 31, when it is observed during 25% of all days.
Moderate rain is the most severe precipitation observed during 38% of those days with precipitation. It is most likely around December 1, when it is observed during 18% of all days.
Either snow is exceptionally unlikely to fall at this location in December or this station does not reliably report precipitation types.
The relative humidity typically ranges from 66% (mildly humid) to 91% (very humid) over the course of a typical December, rarely dropping below 61% (mildly humid) and reaching as high as 99% (very humid).
The air is driest around December 12, at which time the relative humidity drops below 70% (mildly humid) three days out of four; it is most humid around December 23, rising above 87% (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 December, the dew point typically varies from 70°F (muggy) to 75°F (very muggy) and is rarely below 67°F (muggy) or above 78°F (oppressive).
Over the course of December typical wind speeds vary from 2 mph to 15 mph (light air to moderate breeze), rarely exceeding 27 mph (strong breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around December 31, 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 December 7, at which time the average daily maximum wind speed is 14 mph (moderate breeze).