Did you know this?

I have been unable to wake up on time these days and have been terribly late for work. Blaming it on the weather I did a random search on Google on why one feels like sleeping more in winter. The following article is informative and interesting -

Throughout the centuries, poets have described a sense of sadness, loss and lethargy which can accompany the shortening days of fall and winter. Many cultures and religions have winter festivals associated with candles or fire. Many of us notice tiredness, a bit of weight gain, difficulty getting out of bed and bouts of "the blues" as fall turns to winter.However some people experience an exaggerated form of these symptoms. Their depression and lack of energy become debilitating. Work and relationships suffer. This condition, known as Seasonal Affective Disorder (SAD) may affect over 10 million Americans while the milder, "Winter Blues" may affect a larger number of individuals. The typical symptoms of SAD include depression, lack of energy, increased need for sleep, a craving for sweets and weight gain. Symptoms begin in the fall, peak in the winter and usually resolve in the spring. Some individuals experience great bursts of energy and creativity in the spring or early summer. Susceptible individuals who work in buildings without windows may experience SAD-type symptoms at any time of year. Some people with SAD have mild or occasionally severe periods of mania during the spring or summer. If the symptoms are mild, no treatment may be necessary. If they are problematic, then a mood stabilizer such as Lithium might be considered. There is a smaller group of individuals who suffer from summer depression.

Oddly enough, people with seasonal affective disorder often say that they sleep MORE than usual, although it may be more a matter of feeling fatigued and spending extra time in bed rather than actually being asleep. Another peculiarity of SAD is that people with this problem often have particular problems in getting up in the morning. In more severe cases, they may have a clearly delayed sleep phase, that is, they both have trouble falling asleep until late (e.g., long after midnight) and they also wake up late. Like other forms of depression, there is a milder form of SAD called "subsyndromal SAD" which is simply less severe, but it is more common. People with the milder seasonal disorder suffer mild lethargy, gloom, and weight gain in the winter, sometimes oversleeping in the mornings, but not a really disabling depression.
It seems quite clear that many people with SAD have the winter pattern of recurrence at one time in their lives and the more common non seasonal pattern on other occasions.