This report describes the typical weather at the Makkah (Mecca, Saudi Arabia) weather station over the course of an average December. It is based on the historical records from 1984 to 2012. Earlier records are either unavailable or unreliable.
Mecca has a hot desert climate. The area within 25 mi of this station is covered by shrublands (98%) and built-up areas (3%).
The month of December is characterized by gradually falling daily high temperatures, with daily highs decreasing from 91°F to 87°F over the course of the month, exceeding 96°F or dropping below 81°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 21 with 10:50 hours of daylight; the longest day is December 2 with 10:56 hours of daylight.
The earliest sunrise is at 6:42am on December 1; the latest sunset is at 5:50pm on December 31; the latest sunrise is at 6:58am on December 31; the earliest sunset is at 5:38pm on December 1.
Daylight saving time (DST) is not observed in 2012.
The median cloud cover ranges from 18% (mostly clear) to 24% (mostly clear). The trend is for the sky to be becoming cloudier with the median cloud cover increasing by 6% from the start to the end of the month.
On December 16, a representative day, the sky is clear or mostly clear 55% of the time, partly cloudy 20% of the time, and mostly cloudy or overcast 4% of the time.
The average probability that some form of precipitation will be observed in a given day is 7%, with little variation over the course of the month.
Throughout December, the most common forms of precipitation are thunderstorms, moderate rain, and light rain.
Thunderstorms are the most severe precipitation observed during 53% of those days with precipitation. They are most likely around December 2, when it is observed during 4% of all days.
Moderate rain is the most severe precipitation observed during 28% of those days with precipitation. It is most likely around December 27, when it is observed during 2% of all days.
Light rain is the most severe precipitation observed during 14% of those days with precipitation. It is most likely around December 29, when it is observed during 1% 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 37% (comfortable) to 80% (humid) over the course of a typical December, rarely dropping below 27% (dry), or exceeding 91% (very humid).
The air is driest around December 1, at which time the relative humidity drops below 42% (comfortable) three days out of four; it is most humid around December 26, rising above 73% (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 55°F (very comfortable) to 68°F (muggy) and is rarely below 46°F (dry) or above 73°F (very muggy).
Over the course of December typical wind speeds vary from 0 mph to 8 mph (calm to gentle breeze), rarely exceeding 13 mph (moderate breeze).
The highest average wind speed of 3 mph (light air) occurs around December 24, at which time the average daily maximum wind speed is 8 mph (gentle breeze).
The lowest average wind speed of 3 mph (light air) occurs around December 1, at which time the average daily maximum wind speed is 8 mph (gentle breeze).