The S.A.D. STRESS INDEX FOR JANUARY Because of its likelihood of cloud cover, its short days, long nights, and bitter cold weather, January has the worst average on the S.A.D. Stress Index. Conditions continue to be conducive to severe seasonal affective disorders until the middle of February.

  NOVEMBER S.A.D. INDEX November is the first month since March that Index readings consistently indicate a high likelihood of seasonal affective disorders. The average length of November’s night is almost as great as the night’s length in December and January; the weather becomes more severe, and clouds thicken: all those factors equal S.A.D.

 

Seasonal affective disorders increase during the hottest days of the year. Many people who suffer from humidity and high temperatures tend to stay indoors like they do in the winter; consequently, they often experience some of the same S.A.D. symptoms they feel in December or January.