Weather in Guinea Bissau in September
Country-wide climate normals across 15 cities in Guinea Bissau.
How Hot Is Guinea Bissau in September?
Guinea Bissau sees consistently hot September weather — average highs of 30°C, average lows of 24°C, with minimal regional differences. Whether you're in Bissau or one of the coastal cities, conditions feel broadly the same: hot, generally clear, with little night-time relief.
Sunshine in Guinea Bissau in September
Guinea Bissau sees limited sun in September: just 0.8h a day in Bissau, with heavy cloud cover common across most regions. Daylight runs from 6:50 am to 7:00 pm, but persistent grey skies and overcast stretches mean direct sunlight is genuinely scarce. Many days pass without any prolonged sunny spells.
Does It Rain In Guinea Bissau In September?
Heavy seasonal rains saturate Guinea Bissau in September — Bissau averages 416mm of rain across 27 days, with downpours an almost daily feature. The pattern is consistent across most regions, particularly along monsoon-affected coasts. Expect torrential afternoon storms followed by humid heat.
Is Guinea Bissau Humid In September?
Guinea Bissau is enveloped in tropical-thick humidity through September: Bissau averages 85%, and most of the country tracks similarly. The constant moisture makes warm temperatures feel substantially hotter, and even nights bring limited cooling. Light cotton clothing is essential.
Wind In Guinea Bissau In September
Guinea Bissau's September has gentle wind — Bissau averages 12 kph, and the country tracks similarly. Outdoor activity is comfortable, and afternoon thermals add a pleasant breeze in inland areas.
Cloud Cover In Guinea Bissau In September
Heavy overcast covers Guinea Bissau in September: 79% cloud cover in Bissau, with similar grey conditions in most regions. Direct sun is rare, and the pattern is persistent across the country. Coastal and northern regions feel especially heavy.