How does UGI measure weather?

Weather is measured in units called Heating Degree Days (HDDs). Heating Degree Days measure how much lower the normal and actual average daily temperatures were than 65°F, the point where heat is needed for most.

• When Actual Heating Degree Days are more than Normal Heating Degree Days, the weather was colder than normal.
• When Actual Heating Degree Days are less than Normal Heating Degree Days, the weather was warmer than normal.

Actual Heating Degree Days are calculated by taking 65°F (the temperature above which most people don’t need heating) and subtracting the average temperature for that day. For example, an average daily temperature of 45°F would equal 20 Heating Degree Days. An average daily temperature of 75°F would equal 0 Heating Degree Days.