Uganda sits on the equator, so temperatures stay fairly consistent; what changes is rainfall.
June-September and December-February offer the easiest underfoot conditions and are the busiest, most heavily booked months.
April, May and November bring more rain and lusher forest — quieter trails, and in some seasons, reduced permit pricing.
June-September and December-February offer the driest conditions, though gorillas are tracked year-round.
Speak to a safari designer about which months suit your priorities.