Poonhill lies much nearer to Pokhara which is famously called as Cherapunji of Nepal as it receives maximum rainfall in entire Nepal. 
Poonhill weather is usually unpredictable. So, it is wise to know Poonhill weather forecast before going on Poonhill trekking. There are several ways to know about current weather in Poonhill. You can either listen to news on local and national fm stations or you can even log in to websites. Weather predictions done by these websites have been found to be accurate. Daily weather report of Poonhill can be found in websites. 
Four seasons prevails in Poonhill. Winter season lasts from December to February, Spring season exists from March to May, June to August is time for summer season while autumn season continues from September to November. 
October to November and March to April are best seasons for Poonhill Trek as weather remains pretty good in these months. Temperature lies in between approx. 28˚C and 12˚C in Poonhill during September to November. Weather in Poonhill will be pretty cloudy in spring season and the temperature ranges from 20 ˚C to 30˚C. Temperature lies in between 20˚C to 35˚C in summer season. 
http://www.storm247.com/weather/111454204 is one of the reliable website for getting Poonhill weekly weather forecast.