The maximum temperature in Ilam is on average 23°C over the year, with values generally ranging between 9°C in January and 37°C in July. About 748 mm of precipitation falls per year, with a minimum of 1 mm in August and a maximum of 110 mm in March.
The weather is pleasant to stay to Ilam in: April, May, June, July, August, September and October. However, the period when the weather is truly ideal is May, June, September and October.
For hiking and trekking, the best months are March, April, May, September and October.
In terms of crowd levels, the quietest periods are in February, while crowding is high in April, May, June, September, October, December, July and August.