In my neck of the woods it has felt like a pretty poor spring to date. The weather has been overcast, dreary and very wet, which is all highly reminiscent of the last year when summer was effectively rained off.

In our use of language there is a connection made between weather and mood. Gloomy, depressed, cold, sunny, bright, warm are adjectives that are applied to personalities as well as the weather.

Most of us experience feelings of gloominess and lethargy during the winter months, but for some it is more than just feeling a little tired and grumpy. An estimated half a million people suffer from Seasonal Affective Disorder (SAD) every winter. Symptoms include sleep problems, lethargy, overeating, depression, anxiety, loss of libido and mood changes. The main treatment for SAD is exposure to a very high intensity light bulb, although the onset of spring and the longer days usually make symptoms disappear.

But it's not just SAD sufferers who benefit from the longer days; the majority of us tend to be more positive and have a stronger sense of well-being as spring and summer approach. Our mood is better or higher when:

- Humidity is low

- Sunlight is high

- Barometric pressure is high

The effect of temperature on mood is more variable. Our mood is typically better as the temperature goes up but if it gets too hot our mood declines. Furthermore, aggression also increases as temperatures increase, but again declines if it goes too high.

A good spring with sunny weather and higher temperatures boosts our mood more that it would in the summer when these conditions are less of a novelty. A poor spring then means we don' get that surge of positive energy and increased sense of optimism.

Overall the message is a simple one: at this time of year in particular make the most of any good weather you get. We spend over 90% of our time indoors so getting out, if only for half an hour, can have a positive impact.