Abstract: The spatiotemporal changes of the beginning and ending dates of snowfall in Jilin Province were analyzed based on the data of daily precipitation and weather phenomena during the period of 1961-2015. The results showed that there were the spatial differences of the beginning and ending dates of the snowfall in Jilin Province,the beginning time of snowfall in the eastern mountainous area was early but the ending time was late,the ending time of snowfall in the western plain was early but the beginning time was late,the average snowfall dates began on October 22 and ended on April 18 next year. The first spatial pattern of beginning and the ending dates of snowfall was the early (late) pattern in the whole province. The second spatial pattern of beginning dates were the north-south reverse pattern,and the second spatial pattern of ending dates was the east-west reverse pattern. The beginning dates of snowfall occurred mainly in October and November,especially in mid-October,and the ending dates occurred mainly in April and May,especially in mid-April. There was a significant 8-year period of beginning dates of snowfall and a significant 5-year period of ending dates. There was a direct relationship between the beginning and ending dates of snowfall and the atmospheric circulation,the area of the West Pacific subtropical high was smaller and farther northward in the late years of the beginning dates but larger and farther southward in the early years. The area of the West Pacific subtropical high was smaller and farther southward in the late years of the ending dates of snowfall but larger and farther northward in the early years. The beginning and the ending dates of snowfall were also related to the geographical factors,they delayed with the decrease of altitude,while the ending dates became earlier with the increase of latitude and the decrease of altitude.

Key words: snowfall, beginning date, ending date, spatiotemporal variation, Jilin Province