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,
Hail hailstones, described as between the size of bumble bees and ping pong balls, were accompanied by rain and high winds. The hail fell in only the one area, leaving the surrounding area untouched. It fell for one and a half hours between 10 p.m. and 11:30 p.m. A meteorologist for the National Weather Service in Boulder said, "It's a very interesting phenomenon. We saw the storm stall. It produced copious amounts of hail in one small area. It's a meteorological thing." Tractors used to clear the area filled more than 30 dump-truck loads of hail. Research focused on four individual