Truckee’s average 17-degree low and 42-degree high in the winter doesn’t make it a record-holder. It’s the average summer, with 40-degree lows and 79-degree afternoon highs that make the town’s yearly average so cool.

Those chilly summer nights between June and October are caused by cold, dense air flowing down from the surrounding mountains in the basin. That’s particularly true where the official temperature is taken at Truckee Tahoe Airport in the Martis Valley, according to http://www.truckee.com.

Truckee’s extremes range from -31 degrees at its lowest in 1965, to an almost-blistering 99 degrees in 2002, according to http://www.weather.com.

North Lake Tahoe, by contrast, sees less extreme temperatures, according to http://www.weather.com, with a 1972 low of -16 degrees and a 1933 high of 94 degrees in Tahoe City.