This report describes the typical weather at the Colorado Springs Airport (Colorado Springs, United States) weather station over the course of an average September. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Colorado Springs, Colorado has a cold semi-arid steppe climate. The area within 25 mi of this station is covered by grasslands (33%), forests (33%), and shrublands (32%).
The month of September is characterized by rapidly falling daily high temperatures, with daily highs decreasing from 79°F to 69°F over the course of the month, exceeding 87°F or dropping below 56°F only one day in ten.
Over the course of September, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 1:12 hours, implying an average day-over-day decrease of 2.4 minutes.
The shortest day of the month is September 30 with 11:48 hours of daylight; the longest day is September 1 with 13:00 hours of daylight.
The earliest sunrise is at 6:28am on September 1; the latest sunset is at 7:28pm on September 1; the latest sunrise is at 6:54am on September 30; the earliest sunset is at 6:42pm on September 30.
Daylight savings time is observed in 2012 but it neither starts nor ends in September, so the entire month is in daylight time.
The median cloud cover ranges from 21% (mostly clear) to 31% (mostly clear). The trend is for the sky to be clearing with the median cloud cover decreasing by 10% from the start to the end of the month.
On September 29, the clearest day of the month, the sky is clear, mostly clear, or partly cloudy 71% of the time, and overcast or mostly cloudy 24% of the time.
On September 1, the cloudiest day of the month, the sky is overcast, mostly cloudy, or partly cloudy 42% of the time, and clear or mostly clear 52% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around September 1, occurring in 47% of days. Precipitation is least likely around September 30, occurring in 29% of days.
Throughout September, the most common forms of precipitation are thunderstorms and light rain.
Thunderstorms are the most severe precipitation observed during 49% of those days with precipitation. They are most likely around September 1, when it is observed during 28% of all days.
Light rain is the most severe precipitation observed during 30% of those days with precipitation. It is most likely around September 5, when it is observed during 12% of all days.
The likelihood of snow falling is highest around September 30, occurring in 5% of days.
Either snow rarely accumulates at this location in September or snow depth measurements are unavailable or unreliable.
The relative humidity typically ranges from 27% (dry) to 77% (humid) over the course of a typical September, rarely dropping below 13% (very dry) and reaching as high as 97% (very humid).
The air is driest around September 27, at which time the relative humidity drops below 33% (comfortable) three days out of four; it is most humid around September 1, rising above 67% (mildly 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 September, the dew point typically varies from 27°F (dry) to 51°F (very comfortable) and is rarely below 17°F (dry) or above 57°F (comfortable).
Over the course of September typical wind speeds vary from 0 mph to 18 mph (calm to moderate breeze), rarely exceeding 26 mph (strong breeze).
The highest average wind speed of 9 mph (gentle breeze) occurs around September 28, at which time the average daily maximum wind speed is 18 mph (moderate breeze).
The lowest average wind speed of 9 mph (gentle breeze) occurs around September 1, at which time the average daily maximum wind speed is 17 mph (moderate breeze).