Like Senegal, the much larger country that surrounds it, the Gambia has a pleasantly subtropical climate for much of the year, with little or no variation in temperatures, which usually hover around the low 30Cs during the day. Nights, though, can be cool: especially during the main holiday season from November through to March, when they can drop to the mid-teens. Most of the rainfall occurs in the three months of July, August and September, when it can rain on most days, and can also feel uncomfortably hot and humid. The driest month is usually November.
SOURCE: THE GUARDIAN