This report describes the typical weather at the Mount Pleasant Royal Air Force Base (Falkland Islands) weather station over the course of an average January. It is based on the historical records from 1999 to 2012. Earlier records are either unavailable or unreliable.
Falkland Islands has a polar tundra climate. The area within 25 mi of this station is covered by tundra (57%), oceans and seas (40%), and grasslands (2%).
The month of January is characterized by essentially constant daily high temperatures, with daily highs around 59°F throughout the month, exceeding 67°F or dropping below 51°F only one day in ten.
Over the course of January, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 1:15 hours, implying an average day-over-day decrease of 2.4 minutes.
The shortest day of the month is January 31 with 15:21 hours of daylight; the longest day is January 1 with 16:36 hours of daylight.
The earliest sunrise is at 4:39am on January 1; the latest sunset is at 9:15pm on January 1; the latest sunrise is at 5:26am on January 31; the earliest sunset is at 8:47pm on January 31.
Daylight savings time (DST) is not observed in 2012.
The median cloud cover is 83% (mostly cloudy) and does not vary substantially over the course of the month.
On January 16, a representative day, the sky is clear or mostly clear 18% of the time, partly cloudy 17% of the time, and mostly cloudy or overcast 59% of the time.
The average probability that some form of precipitation will be observed in a given day is 74%, with little variation over the course of the month.
Throughout January, the most common forms of precipitation are moderate rain and light rain.
Moderate rain is the most severe precipitation observed during 51% of those days with precipitation. It is most likely around January 15, when it is observed during 39% of all days.
Light rain is the most severe precipitation observed during 35% of those days with precipitation. It is most likely around January 22, when it is observed during 27% of all days.
The likelihood of snow falling is highest around January 1, occurring in 3% of days.
Either snow rarely accumulates at this location in January or snow depth measurements are unavailable or unreliable.
The relative humidity typically ranges from 46% (comfortable) to 94% (very humid) over the course of a typical January, rarely dropping below 31% (comfortable) and reaching as high as 100% (very humid).
The air is driest around January 1, at which time the relative humidity drops below 54% (mildly humid) three days out of four; it is most humid around January 30, rising above 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 typical January, the dew point typically varies from 34°F (dry) to 48°F (dry) and is rarely below 28°F (dry) or above 53°F (very comfortable).
Over the course of January typical wind speeds vary from 6 mph to 29 mph (light breeze to strong breeze), rarely exceeding 38 mph (gale).
The highest average wind speed of 19 mph (fresh breeze) occurs around January 16, at which time the average daily maximum wind speed is 29 mph (strong breeze).
The lowest average wind speed of 18 mph (moderate breeze) occurs around January 31, at which time the average daily maximum wind speed is 28 mph (strong breeze).