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 year. 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%).
Over the course of a year, the temperature typically varies from 75°F to 88°F and is rarely below 73°F or above 89°F.
The warm season lasts from August 7 to October 13 with an average daily high temperature above 87°F. The hottest day of the year is September 4, with an average high of 88°F and low of 79°F.
The cold season lasts from December 19 to March 22 with an average daily high temperature below 84°F. The coldest day of the year is February 29, with an average low of 75°F and high of 83°F.
The length of the day varies significantly over the course of the year. The shortest day is December 21 with 11:18 hours of daylight; the longest day is June 20 with 12:58 hours of daylight.
The earliest sunrise is at 5:35am on May 28 and the latest sunset is at 6:37pm on July 5. The latest sunrise is at 6:33am on January 23 and the earliest sunset is at 5:32pm on November 18.
Daylight saving time (DST) is not observed in 2012.
The median cloud cover ranges from 54% (partly cloudy) to 79% (partly cloudy). The sky is cloudiest on April 17 and clearest on December 7. The clearer part of the year begins around September 12. The cloudier part of the year begins around March 15.
On December 7, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 37% of the time, and overcast or mostly cloudy 27% of the time.
On April 17, the cloudiest day of the year, the sky is overcast, mostly cloudy, or partly cloudy 50% of the time, and clear or mostly clear 7% of the time.
The probability that precipitation will be observed at this location varies throughout the year. Precipitation is most likely around July 30, occurring in 55% of days. Precipitation is least likely around February 21, occurring in 37% of days.
Over the entire year, the most common forms of precipitation are light rain, moderate rain, and thunderstorms.
Light rain is the most severe precipitation observed during 54% of those days with precipitation. It is most likely around August 2, when it is observed during 30% of all days.
Moderate rain is the most severe precipitation observed during 33% of those days with precipitation. It is most likely around November 26, when it is observed during 19% of all days.
Thunderstorms are the most severe precipitation observed during 10% of those days with precipitation. They are most likely around August 29, when it is observed during 15% of all days.
During the warm season, which lasts from August 7 to October 13, there is a 50% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of light rain (48% of days with precipitation have at worst light rain), thunderstorms (26%), and moderate rain (26%).
During the cold season, which lasts from December 19 to March 22, there is a 41% average chance that precipitation will be observed at some point during a given day. When precipitation does occur it is most often in the form of light rain (61% of days with precipitation have at worst light rain) and moderate rain (37%).
Either snow is exceptionally unlikely to fall at any time during the year at this location or this station does not reliably report precipitation types.
The relative humidity typically ranges from 62% (mildly humid) to 94% (very humid) over the course of the year, rarely dropping below 56% (mildly humid) and reaching as high as 100% (very humid).
The air is driest around March 7, at which time the relative humidity drops below 65% (mildly humid) three days out of four; it is most humid around October 4, exceeding 91% (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 year, the dew point typically varies from 68°F (muggy) to 78°F (oppressive) and is rarely below 65°F (mildy humid) or above 79°F (oppressive).
Over the course of the year typical wind speeds vary from 0 mph to 17 mph (calm to moderate breeze), rarely exceeding 76 mph (hurricane).
The highest average wind speed of 11 mph (gentle breeze) occurs around February 6, at which time the average daily maximum wind speed is 17 mph (moderate breeze).
The lowest average wind speed of 6 mph (light breeze) occurs around September 10, at which time the average daily maximum wind speed is 13 mph (moderate breeze).