In Liberia, the climate is tropical, hot and humid all year round, with a rainy season from May to October due to the African monsoon, and pretty frequent rains in the other months, except in the short dry season that runs from December to February, which is more marked in the north.
Along the coast, the rainfall exceeds 3,000 millimeters (118 inches) per year. In the northern part of the coast, in Monrovia, rainfall reaches as high as 5 meters (16.5 feet) per year. In the interior, precipitation is less abundant, and drops in some areas below 2,000 mm (79 in) per year.
In winter, from December to February, the rains are rare in the center and north, and the sun frequently shines, although some showers are still possible. The temperature is high, around 30/32 °C (86/90 °F) during the day, and the humidity remains high, especially along the coast and in the forests of the interior. Sometimes, however, a dry wind able to fill the atmosphere with dust, the Harmattan, blows from the Saharan desert. In the inland hilly regions, and especially in the mountain peaks, the highest of which is Mount Wuteve, 1,440 meters (4,724 feet) high, it can sometimes get cool or a bit cold at night.
In March and April, temperatures slightly rise, and showers become more frequent. Sometimes, it can get very hot, so much so that the temperature can exceed 40 °C (104 °F).
The real monsoon arrives in May, bringing torrential rainfall, especially along the coast. From June to October, cloudiness is frequent, and the daytime temperatures drop below 30 °C (86 °F). Between mid-July and August, the rainy front moves northward, so there is a decrease in rainfall, more evident in the south.
The last month with rainy weather is November, when the rains already decrease sharply compared with the previous months. The temperature increases a little because of the higher amount of sunshine hours, reaching again 30 °C (86 °F) during the day.
The best time to visit Liberia is winter, especially in January and February, since they are the sunniest and least rainy months. The worst period is from May to October, although, between mid-July and late August, rainfall decreases significantly in the south.
In winter: in Monrovia and the northern coast, bring light clothes for the day, a light sweatshirt for the evening, and a scarf for the wind-borne sand and dust. In Greenville and the south coast, add an umbrella or a light raincoat. In inland areas, it may be useful to bring a sweatshirt and a jacket for the evening.
In summer: bring tropics-friendly, light clothing of natural fibers, an umbrella (even though it is not useful for the most intense monsoon rains), a light sweatshirt and a light raincoat for the long and heavy downpours. In inland areas and mountain ranges, you can add a heavier sweatshirt for wet and rainy days.