Avoid: Although Kathmandu has a pleasant climate all year long, the winters are chilly and the rains are consistent enough to hinder the travelling which makes spring and summer the best time to visit Kathmandu.
Tourist season: March to May is the summer season and the temperature rarely rises above 34°C and it hardly rains, so this is the most sought after tourist season of Kathmandu. The months September to November are also a good option as the weather is pleasant and there are many festivities that you can experience.
The typical Kathmandu weather is warm and the nights and mornings are cooler paving a way for a comfortable voyage. The rains and winters although best avoided add a unique charm to the place.