As I hurried to grab my cardigan at the onset of September, I pondered the surprising and profound influence of weather on our mood, eating habits, customs, clothes, and more.

It’s fascinating that the weather can have a more significant impact than our genetic makeup.

It’s also a well-known fact among those in charge of keeping our cities safe that there is a relationship between high temperatures and increased aggressive behaviour. Even more, scientists have proven that violent crime is more common in the warmer regions of the globe. Still, equally, non-violent crime is less common the further south we go to the point that the famous “El Niño” and “La Niña” have been blamed for the variations and incidence of civil conflicts in the regions affected by these phenomena.

Trevor Harley, in 2018, wrote that American scientists had plenty of opportunities to study this subject. They have cities like Dallas, a southern town with plenty of hot days to provide data, sometimes as incomprehensible as showing that the number of assaults rises as the temperature increases above 30ᴼC. Still, as it goes above that, the amount of violence decreases. Similar crime patterns appear during the day, at night, or in France, Spain, and Italy, with significant variations from north to south.

How do we explain these patterns? The best answer is given by Barin and Bell’s NAE (damaging affect escape) model. This model suggests that moderate temperatures can make us feel uncomfortable, which can lead to aggression. However, when temperatures become extreme, our primary motive is escaping discomfort, which can reduce aggression. This pattern is easily observed in situations of road rage, supposedly friendly games where participants are more irascible as the mercury rises, players are more likely to consider the actions of others as being hostile in intent, or the rain responsible for the incidence of domestic violence going up.

Don’t forget the effect of the weather on our mood. Gloomy weather lowers our mood but helps us to focus more and think more deeply, so don’t be surprised that your memory is better on cloudy, rainy days than on sunny days. This is because our brain works harder to remember things when we are in a more focused state, which can be induced by gloomy weather. But how do you explain when your mood is supposed to improve on sunny days? It is straightforward: in good weather, we feel so good that we don’t want to worry about putting a lot of effort into remembering something that will spoil our good mood—why I always believed that our students should be taking exams during the winter months and not when the weather starts to improve in England.

That is not the end of how the weather plays tricks on us; for example, the season in which you are born matters, too, as people born in summer tend to be healthier and more outgoing. The amount of sunshine, temperature, and humidity affect mood and energy levels, and high temperatures make people less anxious and sceptical. For instance, high humidity can make us feel more tired and less energetic, while a sunny day can lift our spirits and make us more sociable. Which explains the problem for many people with SAD as the days become shorter? Seasons have much to do with how we think, feel, and behave.

The influence of weather is not just a matter of curiosity; it has practical implications for our daily lives. Even our shoppers have proven this through mood and memory tests conducted by retailers. On a rainy day, we tend to recall good memories and have fewer false memories of objects that weren’t present. This is a crucial consideration for retailers when planning sales or events. For us, it’s a reminder that not everything is perfect when the sun shines, especially now that we know that sunshine can be blamed for our numerous senior moments!