This report describes the typical weather at the Churchill Airport (Churchill, Manitoba, Canada) weather station over the course of an average October. It is based on the historical records from 1977 to 2012. Earlier records are either unavailable or unreliable.
Churchill, Manitoba has a humid subarctic continental climate with cool summers and no dry season. The area within 25 mi of this station is covered by tundra (45%), oceans and seas (44%), shrublands (7%), and lakes and rivers (3%).
The month of October is characterized by very rapidly falling daily high temperatures, with daily highs decreasing from 42°F to 27°F over the course of the month, exceeding 53°F or dropping below 15°F only one day in ten.
Over the course of October, the length of the day is very rapidly decreasing. From the start to the end of the month, the length of the day decreases by 2:32 hours, implying an average day-over-day decrease of 4.9 minutes.
The shortest day of the month is October 31 with 8:54 hours of daylight; the longest day is October 1 with 11:26 hours of daylight.
The earliest sunrise is at 7:23am on October 1; the latest sunset is at 6:49pm on October 1; the latest sunrise is at 8:33am on October 31; the earliest sunset is at 5:27pm on October 31.
Daylight savings time is observed in 2012 but it neither starts nor ends in October, so the entire month is in daylight time.
The median cloud cover is 97% (overcast) and does not vary substantially over the course of the month.
On October 16, a representative day, the sky is clear or mostly clear 10% of the time, partly cloudy 10% of the time, and mostly cloudy or overcast 80% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around October 26, occurring in 82% of days. Precipitation is least likely around October 1, occurring in 76% of days.
Throughout October, the most common forms of precipitation are light snow, moderate snow, and light rain.
Light snow is the most severe precipitation observed during 58% of those days with precipitation. It is most likely around October 31, when it is observed during 58% of all days.
Moderate snow is the most severe precipitation observed during 16% of those days with precipitation. It is most likely around October 27, when it is observed during 14% of all days.
Light rain is the most severe precipitation observed during 15% of those days with precipitation. It is most likely around October 1, when it is observed during 21% of all days.
The likelihood of snow falling is highest around October 31, occurring in 74% of days.
Accumulation at this location in October is unlikely. The chances of there being snow on the ground are highest around October 31, occurring 32% of the time.
The snow is typically at its deepest on October 31, with a median depth of 2.6"; the depth exceeds 6.4" only one year out of ten.
The relative humidity typically ranges from 67% (mildly humid) to 95% (very humid) over the course of a typical October, rarely dropping below 50% (mildly humid) and reaching as high as 100% (very humid).
The air is driest around October 1, at which time the relative humidity drops below 76% (humid) three days out of four; it is most humid around October 18, rising above 91% (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 October, the dew point typically varies from 12°F (dry) to 36°F (dry) and is rarely below -2°F (dry) or above 44°F (dry).
Over the course of October typical wind speeds vary from 5 mph to 21 mph (light breeze to fresh breeze), rarely exceeding 33 mph (high wind).
The highest average wind speed of 15 mph (moderate breeze) occurs around October 7, at which time the average daily maximum wind speed is 21 mph (fresh breeze).
The lowest average wind speed of 14 mph (moderate breeze) occurs around October 15, at which time the average daily maximum wind speed is 20 mph (fresh breeze).