Average Weather in September in Iisalmi Finland
Daily high temperatures decrease by 11°F, from 59°F to 49°F, rarely falling below 42°F or exceeding 68°F.
Daily low temperatures decrease by 7°F, from 47°F to 40°F, rarely falling below 31°F or exceeding 54°F.
For reference, on July 23, the hottest day of the year, temperatures in Iisalmi typically range from 54°F to 70°F, while on February 3, the coldest day of the year, they range from 8°F to 20°F.
Average High and Low Temperature in September
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on September. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in September
The month of September in Iisalmi experiences rapidly increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 57% to 72%.
The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 43% of the time.
For reference, on December 16, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 85%, while on July 19, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 53%.
Cloud Cover Categories in September
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Iisalmi, the chance of a wet day over the course of September is essentially constant, remaining around 32% throughout.
For reference, the year's highest daily chance of a wet day is 40% on July 28, and its lowest chance is 17% on February 24.
Probability of Precipitation in September
The average sliding 31-day rainfall during September in Iisalmi is gradually decreasing, starting the month at 2.5 inches, when it rarely exceeds 3.9 inches or falls below 1.2 inches, and ending the month at 2.2 inches, when it rarely exceeds 3.4 inches or falls below 1.0 inches.
Average Monthly Rainfall in September
Over the course of September in Iisalmi, 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 3 hours, 2 minutes, implying an average daily decrease of 6 minutes, 17 seconds, and weekly decrease of 43 minutes, 56 seconds.
The shortest day of the month is September 30, with 11 hours, 27 minutes of daylight and the longest day is September 1, with 14 hours, 29 minutes of daylight.
Hours of Daylight and Twilight in September
The earliest sunrise of the month in Iisalmi is 5:55 AM on September 1 and the latest sunrise is 1 hour, 21 minutes later at 7:16 AM on September 30.
The latest sunset is 8:24 PM on September 1 and the earliest sunset is 1 hour, 41 minutes earlier at 6:43 PM on September 30.
Daylight saving time is observed in Iisalmi during 2021, but it neither starts nor ends during September, so the entire month is in daylight saving time.
For reference, on June 21, the longest day of the year, the Sun rises at 2:52 AM and sets 20 hours, 41 minutes later, at 11:33 PM, while on December 21, the shortest day of the year, it rises at 9:56 AM and sets 4 hours, 26 minutes later, at 2:22 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in September
The figure below presents a compact representation of key lunar data for September 2021. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.
Moon Rise, Set & Phases in September
The chance that a given day will be muggy in Iisalmi is essentially constant during September, remaining around 0% throughout.
For reference, on July 27, the muggiest day of the year, there are muggy conditions 2% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in September
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Iisalmi is essentially constant during September, remaining within 0.2 miles per hour of 5.1 miles per hour throughout.
For reference, on January 25, the windiest day of the year, the daily average wind speed is 6.4 miles per hour, while on July 30, the calmest day of the year, the daily average wind speed is 4.5 miles per hour.
Average Wind Speed in September
The hourly average wind direction in Iisalmi throughout September is predominantly from the south, with a peak proportion of 37% on September 26.
Wind Direction in September
The growing season in Iisalmi typically lasts for 4.6 months (142 days), from around May 15 to around October 3, rarely starting before April 28 or after June 1, and rarely ending before September 12 or after October 23.
The month of September in Iisalmi is more likely than not fully within the growing season, with the chance that a given day is in the growing season rapidly decreasing from 97% to 58% over the course of the month.
Time Spent in Various Temperature Bands and the Growing Season in September
The average accumulated growing degree days in Iisalmi are gradually increasing during September, increasing by 75°F, from 1,000°F to 1,075°F, over the course of the month.
Growing Degree Days in September
The average daily incident shortwave solar energy in Iisalmi is rapidly decreasing during September, falling by 1.8 kWh, from 3.3 kWh to 1.5 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in September
For the purposes of this report, the geographical coordinates of Iisalmi are 63.559 deg latitude, 27.191 deg longitude, and 308 ft elevation.
The topography within 2 miles of Iisalmi contains only modest variations in elevation, with a maximum elevation change of 184 feet and an average elevation above sea level of 302 feet. Within 10 miles also contains only modest variations in elevation (486 feet). Within 50 miles contains only modest variations in elevation (948 feet).
The area within 2 miles of Iisalmi is covered by water (41%), artificial surfaces (38%), and trees (15%), within 10 miles by trees (64%) and cropland (21%), and within 50 miles by trees (77%) and water (11%).
This report illustrates the typical weather in Iisalmi, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in Iisalmi.
For each station, the records are corrected for the elevation difference between that station and Iisalmi according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Iisalmi is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Iisalmi and a given station.
Time zones for airports and weather stations are provided by AskGeo.com .