Trevelin ground for long periods of time. Winters are stormy with frequent rain, sleet and snow while summers are cool, windy and relatively dry. Mean annual precipitation is . The precipitation pattern resembles a Mediterranean one, where most (75%) of the precipitation is concentrated from April to August, the cooler months with a dry period from September to March. Snowfall can occur during the colder months while rainfall predominates in warmer months; hail rarely occurs. The mean temperature in Trevelin ranges from in July, the coldest month to in January, the warmest month. Frosts can occur at anytime, even in summer,
February 9–10, 2010 North American blizzard and out of Bradley International Airport, and Metro North operated trains on a reduced schedule on February 10. Around the local Philadelphia area, snow began during the early evening on the 9th. As warmer air moved in aloft, the snow changed to sleet and freezing rain between 3 a.m. and 6 a.m. EST on the 10th. Surface temperatures responded slower and the sleet and freezing rain changed over to rain during the morning of the 10th. Some sleet mixed in from time to time. As the low pressure system moved northeast of the region, the rain changed back to snow