This report describes the typical weather at the Denver International Airport (Denver, Colorado, United States) weather station over the course of an average January. It is based on the historical records from 1995 to 2012. Earlier records are either unavailable or unreliable.
Denver, Colorado has a cold semi-arid steppe climate. The area within 25 mi of this station is covered by grasslands (86%), built-up areas (10%), and croplands (3%).
The month of January is characterized by essentially constant daily high temperatures, with daily highs around 43°F throughout the month, exceeding 59°F or dropping below 27°F only one day in ten.
Over the course of January, the length of the day is gradually increasing. The shortest day of the month is January 1 with 9:25 hours of daylight; the longest day is January 31 with 10:08 hours of daylight.
The earliest sunrise is at 7:08am on January 31; the latest sunset is at 5:16pm on January 31; the latest sunrise is at 7:21am on January 4; the earliest sunset is at 4:45pm on January 1.
Daylight savings time is observed in 2012 but it neither starts nor ends in January, so the entire month is in standard time.
The median cloud cover is 67% (partly 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 25% of the time, partly cloudy 25% of the time, and mostly cloudy or overcast 46% of the time.
The average probability that some form of precipitation will be observed in a given day is 25%, with little variation over the course of the month.
Throughout January, the most common forms of precipitation are light snow and moderate snow.
Light snow is the most severe precipitation observed during 77% of those days with precipitation. It is most likely around January 16, when it is observed during 20% of all days.
Moderate snow is the most severe precipitation observed during 14% of those days with precipitation. It is most likely around January 1, when it is observed during 4% of all days.
The likelihood of snow falling is highest around January 16, occurring in 24% of days.
Accumulation at this location in January is unlikely. The chances of there being snow on the ground are highest around January 31, occurring 11% of the time.
The snow is typically at its deepest on January 20, with a median depth of 2.0"; the depth exceeds 2.7" only one year out of ten.
The relative humidity typically ranges from 37% (comfortable) to 80% (humid) over the course of a typical January, rarely dropping below 15% (very dry) and reaching as high as 97% (very humid).
The air is driest around January 16, at which time the relative humidity drops below 46% (comfortable) three days out of four; it is most humid around January 27, rising above 71% (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 8°F (dry) to 21°F (dry) and is rarely below -4°F (dry) or above 29°F (dry).
Over the course of January typical wind speeds vary from 0 mph to 17 mph (calm to moderate breeze), rarely exceeding 26 mph (strong breeze).
The highest average wind speed of 10 mph (gentle breeze) occurs around January 3, at which time the average daily maximum wind speed is 17 mph (moderate breeze).
The lowest average wind speed of 10 mph (gentle breeze) occurs around January 22, at which time the average daily maximum wind speed is 17 mph (moderate breeze).