Each climate gauge is based on daily data from the ThreadEx dataset.
The long-term time series of each variable is sorted and divided into four segments, each containing one quarter of the total available data.
The lowest 25% of the values are considered below normal (blue) and the highest 25% are considered above normal (red).
The remaining 50% of the values are divided in half to give the slightly below (green) and slightly above normal (gold) categories.
In cases where the slightly below and slightly above categories contain the same values, they are combined into a single normal (tan) category.
The slightly larger, highlighted segment shows the category in which the current year falls. A new record (gray shading) occurs when either the current year’s value falls above the highest or below the lowest historical value. Each variable’s historical record can be viewed and the data downloaded by clicking on the gauge.