Degree-Day Explorer

Each county, state or region is coloured by its weighted degree days from the chosen model run: heating degree days (HDD) for heating demand, cooling degree days (CDD) for cooling, or their total (TDD). Degree days are computed for every ensemble member at every grid cell, then weighted to each county by where people live (population), where homes heat with gas (gas heating) or where power plants burn gas (power burn), so a state's value reflects demand rather than empty land.

Show switches between the value itself, its departure from the 1991–2020 normal for the same days (blue below normal, red above), the change from the previous run of the same model (red: the new run added degree days), or the difference from another model. Period sums a single day, a rolling seven-day window, or the whole run. Scales are fixed for the whole run by default, so playing the loop shows real change rather than a palette re-fitting itself each day.