Cold

Degree Days A degree day is a measure of coldness. The colder the weather the higher the DD value.

For more information about Degree Days visit Degree Days – An Introduction

I take temperature readings each day and over the past years I have calculated the D-Days for each week. A week on week comparison can't ever say much but a cumulative plot will show a trend over time. The cumulative plot is just the total D-Days for the current week added to the the total for the year so far.

My heating year starts in September but I have started the data at the end of May / beginning of June.

All the readings have been made by me at my home on the Isle of Wight UK. This years data can be found here.

The sheet below compares this year with the 10 year average. Last year (21/22), which was very mild, the total Degree Days (June to May) was 1, 484 the average over 10 years is 1,638 .

How should you use this information? My paper entitled "Degree Days, What are they & how do you use them ?" May help

Essentially, the colder the outside air temperature, the more energy it takes to heat a building. Check the sheet and graph below, if the weather gets colder this winter (remember last year was very mild), you should expect your heating bill to increase.

You can find the Degree Day data for your area here .

Below is a graph that shows the year so far

The week numbers are weeks since 1 June

All good fun !