Gondar sits at around 2,200 metres elevation, which keeps temperatures moderate year-round — rarely above 25°C and rarely cold. The main Ethiopian rainy season (kiremt) runs from June through September, bringing heavy afternoon rains that can make roads to the Simien Mountains difficult. October to January is the classic window: clear skies, green landscapes after the rains, and pleasant walking weather.
Timkat (Ethiopian Epiphany) falls in mid-January (usually January 19–20) and is the single best reason to time a visit. Gondar's celebrations are considered the most theatrical in Ethiopia. Priests carry the tabot (a replica of the Ark of the Covenant) in candlelit procession to the Fasilidas Baths on the eve of the festival; the following morning, the pool is blessed and the faithful wade in. The streets are packed with white-clad worshippers and the singing continues through the night. Book accommodation months in advance.
Fasika (Ethiopian Easter) in April or May is another major celebration, with midnight church services and feasting. The exact date moves with the Ethiopian Orthodox calendar.
The shoulder months of February–March and October–November combine good weather with smaller crowds. Avoid the rainy season if you plan to trek in the Simiens.