Solar Spring is Here

Here's a plot of daily high temperatures over the past five weeks at Fairbanks Airport (475 feet MSL) and Keystone Ridge (1600' MSL). The green line is the difference between the two (Airport minus Ridge). Up through late February, high temperatures were consistently lower at the Airport than on the Ridge. Since the end of February, the rapidly increasing solar insolation is breaking the nocturnal temperature inversion almost every day now, and this is a useful definition of spring in Interior Alaska.