This report describes the typical weather at the Sangster International Airport (Montego Bay, Jamaica) weather station over the course of an average January. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Montego Bay has a tropical monsoon climate with short dry season. The area within 25 mi of this station is covered by oceans and seas (55%) and forests (41%).
The month of January is characterized by essentially constant daily high temperatures, with daily highs around 83°F throughout the month, exceeding 85°F or dropping below 80°F only one day in ten.
Over the course of January, the length of the day is essentially constant. The shortest day of the month is January 1 with 11:03 hours of daylight; the longest day is January 31 with 11:19 hours of daylight.
The earliest sunrise is at 6:44am on January 1; the latest sunset is at 6:05pm on January 31; the latest sunrise is at 6:47am on January 18; the earliest sunset is at 5:46pm on January 1.
Daylight saving time (DST) is not observed in 2012.
The median cloud cover is 34% (mostly clear) and does not vary substantially over the course of the month.
On January 16, a representative day, the sky is clear or mostly clear 49% of the time, partly cloudy 18% of the time, and mostly cloudy or overcast 17% of the time.
The average probability that some form of precipitation will be observed in a given day is 35%, 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 56% of those days with precipitation. It is most likely around January 16, when it is observed during 20% of all days.
Light rain is the most severe precipitation observed during 36% of those days with precipitation. It is most likely around January 10, when it is observed during 13% of all days.
Either snow is exceptionally unlikely to fall at this location in January or this station does not reliably report precipitation types.
The relative humidity typically ranges from 64% (mildly humid) to 90% (very humid) over the course of a typical January, rarely dropping below 55% (mildly humid) and reaching as high as 100% (very humid).
The air is driest around January 29, at which time the relative humidity drops below 69% (mildly humid) three days out of four; it is most humid around January 6, rising above 84% (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 66°F (muggy) to 73°F (very muggy) and is rarely below 61°F (comfortable) or above 77°F (oppressive).
Over the course of January typical wind speeds vary from 0 mph to 19 mph (calm to fresh breeze), rarely exceeding 25 mph (strong breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around January 1, at which time the average daily maximum wind speed is 18 mph (fresh breeze).
The lowest average wind speed of 9 mph (gentle breeze) occurs around January 16, at which time the average daily maximum wind speed is 18 mph (fresh breeze).