Spring fever is synonymously used for the madness caused by the deprival of snow piles around the corners of one's periphery.
In Northern hemisphere, the feelings of confined-ness of the winter creates a virtual pressure on people to get out.
The above may be taken as the psychological causes for it.
However, there has to be some ecological aspects of it.
The physiological causes are explained as follow:
Although the causes of spring fever have not yet been fully resolved, hormone balance may play a role. According to this theory the body’s reserves of the “happiness hormone” serotonin, whose production depends on daylight, become exhausted over the winter, making it especially easy for the “sleep hormone” melatonin to have its effect. When the days become longer in springtime, the body readjusts its hormone levels, and more endorphin, testosterone and estrogen are released. This changeover puts a heavy strain on the body, which responds with a feeling of tiredness.In addition, temperatures usually fluctuate greatly in springtime. When temperatures rise, blood pressure drops, since the blood vessels expand. Food also plays a role. In winter one tends to consume more calories, fat and carbohydrates than in summer. But during the hormone adjustment period the body requires more vitamins and proteins instead. [Source: Wikipedia]
I am eagerly waiting for it!