September marks a relief from the intensive heat, offering transition from summer to fall. The onset of cooler weather is marked by a decreased number of daylight hours. Relative humidity tends to increase, and the UV index decreases, allowing more comfortable outdoor activities. A decline in the maximum temperature to 28.6°C (83.5°F) and a fall in minimum to 14.4°C (57.9°F) is noted, as the days become perceptibly cooler. Owing to the reduced heat, rainfall gradually increases, though the rainfall days still remain noticeably few.
Temperature
The onset of September in
Larissa entails a subtle temperature shift, as the average high-temperature eases from a hot 32.9°C (91.2°F) in
August to a warm 28.6°C (83.5°F). From significant daily highs, Larissa's nights in September cool down to an average low-temperature of 14.4°C (57.9°F).
Heat index
The average heat index in September is calculated to be a tropical 30°C (86°F). Long-standing exposure coupled with ongoing activity could result in exhaustion, possibly causing heat cramps.
Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. The direct sun can potentially cause the heat index to increase by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'apparent temperature' or 'real feel', is a calculation that merges air temperature and relative humidity to depict the sensation of warmth. The impact of weather is personal, differing among a variety of people based on differences in body mass, height, and the level of physical exertion. Be aware that direct exposure to sunlight increases heat impact and may raise the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are primarily vital for children. Children frequently underestimate the necessity to rest and hydrate. Thirst is a late sign of dehydration - thus, it is vital to stay hydrated, particularly during lengthy physical exercises.
Humidity
In Larissa,
Greece, the average relative humidity in September is 58.6%.
Rainfall
September is the month with the least rainfall. Rain falls for 2 days and accumulates 13mm (0.51") of precipitation.
Daylight
In September, the average length of the day is 12h and 27min.
On the first day of September, sunrise is at 06:58 and sunset at 20:01. On the last day of the month, sunrise is at 07:25 and sunset at 19:14 EEST.
Sunshine
In Larissa, the average sunshine in September is 8.3h.
UV index
In September, the average daily maximum UV index in Larissa is 6. A UV Index of 6 to 7 symbolizes a high health vulnerability from unprotected exposure to Sun's UV rays for the average person.
Note: The maximum UV index of 6 during September leads to these instructions:
Beware of overexposure. Fair-skinned individuals risk burning in less than 20 minutes. Be aware that the sun's UV radiation is strongest between 10 a.m. and 4 p.m. and try to reduce direct sun exposure during this period as much as possible. Sun-protective clothing, a long-sleeved shirt and pants, a wide-brimmed hat, and UVA and UVB-blocking sunglasses are particularly helpful in blocking UV radiation's harmful effects.