This report describes the typical weather at the Riga International Airport (Riga, Latvia) weather station over the course of an average December. It is based on the historical records from 1995 to 2012. Earlier records are either unavailable or unreliable.
Riga has a humid continental climate with warm summers and no dry season. The area within 25 mi of this station is covered by croplands (43%), oceans and seas (26%), forests (15%), grasslands (10%), and built-up areas (3%).
The month of December is characterized by falling daily high temperatures, with daily highs ranging from 36Â°F to 31Â°F over the course of the month, exceeding 45Â°F or dropping below 19Â°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 26 with 6:45 hours of daylight; the longest day is December 1 with 7:13 hours of daylight.
The earliest sunrise is at 8:37am on December 1; the latest sunset is at 3:53pm on December 31; the latest sunrise is at 9:03am on December 27; the earliest sunset is at 3:42pm on December 15.
Daylight savings time is observed in 2012 but it neither starts nor ends in December, so the entire month is in standard time.
The median cloud cover is 100% (overcast) and does not vary substantially over the course of the month.
On December 16, a representative day, the sky is clear or mostly clear 2% of the time, partly cloudy 5% of the time, and mostly cloudy or overcast 81% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around December 31, occurring in 78% of days. Precipitation is least likely around December 1, occurring in 74% of days.
Throughout December, the most common forms of precipitation are moderate snow, light snow, and light rain.
Moderate snow is the most severe precipitation observed during 37% of those days with precipitation. It is most likely around December 31, when it is observed during 32% of all days.
Light snow is the most severe precipitation observed during 26% of those days with precipitation. It is most likely around December 30, when it is observed during 24% of all days.
Light rain is the most severe precipitation observed during 25% of those days with precipitation. It is most likely around December 1, when it is observed during 25% of all days.
The likelihood of snow falling is highest around December 31, occurring in 58% of days.
Either snow rarely accumulates at this location in December or snow depth measurements are unavailable or unreliable.
The relative humidity typically ranges from 79% (humid) to 97% (very humid) over the course of a typical December, rarely dropping below 66% (mildly humid) and reaching as high as 100% (very humid).
The air is driest around December 10, at which time the relative humidity drops below 86% (very humid) three days out of four; it is most humid around December 19, rising above 96% (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 19Â°F (dry) to 33Â°F (dry) and is rarely below 3Â°F (dry) or above 43Â°F (dry).
Over the course of December typical wind speeds vary from 3 mph to 13 mph (light breeze to moderate breeze), rarely exceeding 20 mph (fresh breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around December 3, at which time the average daily maximum wind speed is 13 mph (moderate breeze).
The lowest average wind speed of 8 mph (gentle breeze) occurs around December 28, at which time the average daily maximum wind speed is 13 mph (moderate breeze).