Atlanta has a humid subtropical climate with four distinct seasons and abundant rainfall year round. This is typical of its location in south-eastern USA. It is also susceptible to tornados. Tornado season lasts from March till mid May. Atlanta is the capital and cultural centre of Georgia. While its winters are bearably mild, it is best enjoyed in warm weather and is known to most in the peak of its sweltering summer heat.
Summer, from June till September, sees the average high temperature rising from the already baking high 20s into the low 30s, and average lows sitting around 20°C. September is slightly cooller than the peak months with an average high of 28°C and an average low of 17°C – still pretty hot! Atlanta has good sunshine levels throughout the year, peaking in June with an average of ten hours per day which slowly decreases to eight by mid August. Rainfall is evenly spread across the year but has a slight peak in July – don’t get caught without a jacket. When packing for a visit to Atlanta in the summer, remember you aren’t just packing for the weather: it may be hot outside but indoors the aircon is usually turned on full blast.
Autumn, in October and November, remains warm with average high temperatures dropping down through the 20s and into the high teans. October has an average high of 23°C and November one of 18°C, while average lows get down to a mild 11°C and a chilly 6°C respectively; while the days are bound to be warm, night times see the temperature plummet. Rainfall levels sit around 90mm per month and precipitation usually occurs in heavy storms. Sunshine levels dip slightly, getting down to an average of six hours per day in November.
Winter, from December till February, is cool and sometimes quite cold, but it is quite bright and precipitation generally falls as rain rather than snow. The average high temperature drops into the low teens and the average low hovers around freezing. January tends to be the coldest month with an average high of 10°C and an average low of 0°C. It is slightly wetter with the monthly average rainfall climing to around 120mm. Sunshine averages at around five hours per day though it is brighter towards the end of the season.
Spring, from March till May, sees temperatures quickly climbing towards the summer highs. March has an average high of 18°C, April 23°C and May 27°C. At night it remains mild with average lows climbing from 6°C in March to 10°C in April and 14°C in May. Rainfall peaks again in March and as it lessens sunshine levels rush back up to nine hours per day. Spring is tornado season but, as you might expect, the city is well-equipped with warning sirens.
The city sits in the foothills of the Appalachian Mountains at an elevation of 1,010 feet above sea level, which makes Atlanta cooler year round than more southerly, lower-lying locations in Georgia. The mountains somewhat block cold northerly winds from the city, keeping it warmer and drier than locations to the north and higher up in the mountains. However, they also create a corridor for winds coming from any direction, funnelling them into dramatic weather systems that can cause havoc in northeastern US, and creating a localised ‘tornado alley’ affecting many Georgian counties, including Atlanta itself, especially its north and western areas. The city also sits on the Eastern Continental Divide which causes water on the northwest side to flow towards the Gulf of Mexico, and any precipitation falling on the southeast side to run towards the Atlantic Ocean. These two great bodies of water greatly affect Atlanta’s weather throughout the year, moderating its temperature and providing rainfall and humidity. The city’s proximity to mountains, a gulf and an ocean, mean that its weather is highly changeable from moment to moment, particularly in the winter.
Severe Weather in Atlanta
In mid March 2008 the southern states in Tornado Alley were warned of a slight risk of severe weather. Between the 14th and 15th Atlanta was hit by a succession of devastating tornadoes causing an estimated quarter of a million dollars worth of damage across the city. An astounding 45 tornadoes were recorded. Only three fatalities were caused by this onslaught.
Aside from tornadoes, Atlanta has also been known to suffer from droughts and flooding. Tornados and the remnants of hurricanes travelling northwards can cause unprecedented rainfall, and, as global warming unsettles climates everywhere, the trend of regular rainfall cannot be relied upon. Droughts have been known to be so extreme that extensive forest fires spring up, affecting the entire state. Water management is a constant problem for the city.