Dear sir, We have 19 Years of weather data. We have the dssat manual, and according to dssat manual our format is correct.We have tha data for 40 stations and we are facing this problem for a few stations only . Our problem is that while generating the ".cli" files,from the weather data we are getting zero values of alpha even whan RTOT (total rainfall 19years mean) and RNUM (No. of rainy days) is not zero. Also for a few stations we are getting absurd values of alpha (like -178354673.000) because of which the model is givng error in reading ".cli" file and we are unable to generate weather data. Anamika Arora IIT Delhi _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.