As someone who has extensive experience measuring temperature, understand that any discussion of temperature outside a lab is silly if it doesn’t say, ±2°F. (or ±1°C).
Anomalies, averages, deviations, et al. They all are impractical at better than two degrees Fahrenheit. Any discussion of temperature values of less than 2°F probably involves ocean-front property in Arizona. Don’t be fooled.
The first principle is that you must not fool yourself — and you are the easiest person to fool.
Richard Phillips Feynman (May 11, 1918 – February 15, 1988)