Trends of the first and last snow date and the length of snow season, defined by the time period between first and last snow date, during 1937--94 over northern Asia are examined. The length of snow season over North Central and Northwest Asia has increased by about 4 days per decade during the study period. The increased length of the snow season is due to earlier snowfalls at the beginning of the season and to a lesser extent to later last snowfalls at the end of the season. ¿ 2001 American Geophysical Union