The best time to go to Touba is during the dry season, which runs from November to May.
During these months, the weather is more pleasant, with lower humidity and less rainfall, making it ideal for exploring the city's key sites. Temperatures are generally warm but comfortable, averaging around 25-30°C (77-86°F), so you can enjoy walking around without the intensity of the rainy season's heat and moisture.
This period also avoids the major annual pilgrimage, the Grand Magal of Touba, which typically occurs in late September or early October. While a significant cultural event, the Magal attracts millions of pilgrims, leading to extremely crowded conditions, limited accommodation availability, and significantly higher prices. Visiting outside of this time ensures a more relaxed and accommodating experience.