This report describes the typical weather at the Bacacheri Airport (Curitiba, Brazil) weather station over the course of an average September. It is based on the historical records from 2008 to 2012. Earlier records are either unavailable or unreliable.
Curitiba has a mild humid temperate climate with warm summers and no dry season. The area within 25 mi of this station is covered by croplands (57%), forests (17%), grasslands (11%), built-up areas (9%), and shrublands (4%).
The month of September is characterized by gradually falling daily high temperatures, with daily highs ranging from 71Â°F to 69Â°F over the course of the month, exceeding 79Â°F or dropping below 61Â°F only one day in ten.
Over the course of September, the length of the day is gradually increasing. The shortest day of the month is September 1 with 11:37 hours of daylight; the longest day is September 30 with 12:20 hours of daylight.
The earliest sunrise is at 5:57am on September 30; the latest sunset is at 6:17pm on September 30; the latest sunrise is at 6:28am on September 1; the earliest sunset is at 6:06pm on September 1.
Daylight savings time is observed in 2012 but it neither starts nor ends in September, so the entire month is in standard time.
The median cloud cover ranges from 74% (partly cloudy) to 79% (partly cloudy).
On September 15, a representative day, the sky is clear or mostly clear 11% of the time, partly cloudy 6% of the time, and mostly cloudy or overcast 39% of the time.
The probability that precipitation will be observed at this location varies throughout the month. Precipitation is most likely around September 30, occurring in 46% of days. Precipitation is least likely around September 2, occurring in 37% of days.
Throughout September, the most common forms of precipitation are thunderstorms, light rain, and drizzle.
Thunderstorms are the most severe precipitation observed during 40% of those days with precipitation. They are most likely around September 29, when it is observed during 20% of all days.
Light rain is the most severe precipitation observed during 38% of those days with precipitation. It is most likely around September 4, when it is observed during 17% of all days.
Drizzle is the most severe precipitation observed during 18% of those days with precipitation. It is most likely around September 24, when it is observed during 8% of all days.
Either snow is exceptionally unlikely to fall at this location in September or this station does not reliably report precipitation types.
The relative humidity typically ranges from 47% (comfortable) to 97% (very humid) over the course of a typical September, rarely dropping below 32% (comfortable) and reaching as high as 100% (very humid).
The air is driest around September 3, at which time the relative humidity drops below 55% (mildly humid) three days out of four; it is most humid around September 26, rising above 95% (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 September, the dew point typically varies from 46Â°F (dry) to 57Â°F (comfortable) and is rarely below 40Â°F (dry) or above 61Â°F (comfortable).
The time of the month between September 1 and September 30 is the most comfortable, with dew points that are neither too dry nor too muggy.
Over the course of September typical wind speeds vary from 2 mph to 12 mph (light air to gentle breeze), rarely exceeding 20 mph (fresh breeze).
The highest average wind speed of 7 mph (light breeze) occurs around September 18, at which time the average daily maximum wind speed is 12 mph (gentle breeze).
The lowest average wind speed of 6 mph (light breeze) occurs around September 2, at which time the average daily maximum wind speed is 12 mph (gentle breeze).