Now Available: 2025 Heating Degree Day Analyses

A heating degree day (HDD) is a measure of how cold a location is. It’s derived by comparing the average outdoor temperature to a baseline of 65 degrees. More extreme cold temperatures result in a higher number of HDDs, which typically translate to an increased demand for space heating by energy consumers.

NPGA has produced updated data sets that detail the number of HDDs that occurred during each month of the heating season (October-March) over the past 3 years, as well as each month’s 10-year average, broken down by Census Division. As members continue to evaluate their potential supply and demand scenarios for the upcoming heating season, they can use these data to better understand what the needs of their customers were in previous years.  

For example, in January 2025 HDDs across every Census Division were well above the 10-year average. That month the U.S. saw 947 HDDs, compared to a 10-year average of only 836 HDDs – an increase of 13.2%. As a result, U.S. propane consumption reached 1.48 million barrels per day in January 2025 – the highest level of domestic consumption for any month since February 2007, and the highest level for any January since 2005.

These data sets can be found under the Supply and Logistics section on the Member Dashboard of NPGA’s website. For more information, contact NPGA’s Director of State Affairs, Jacob Peterson.