Abstract: A weather instrument and method for comparing current temperature at a location to historical temperatures at the location. In one embodiment, the weather instrument includes a temperature sensor producing a temperature signal; a clock producing a periodic time signal; a processor in communication with the temperature sensor and the clock, the processor producing hourly mean temperature measurements from the temperature sensor in response to the periodic time signal, and a memory in communication with the processor. The memory stores hourly mean temperature measurements and historical temperature data for the location. In one embodiment, the method includes the steps of producing hourly mean temperature measurements from a temperature sensor in response to said periodic time signal and storing said hourly mean temperature measurements and historical temperature data for said location in a memory.