How Cold Does it Get By Location?

This map shows you how cold each United States location is. More specifically, when a place gets cold, how cold does it get? The darker color is colder and the lighter color is more less cold. The coloration is normalized using US data. You can mouse over each dot to see a given location’s data.

Each location on the map shows what is called the 99% heating dry bulb temperature, which represents the outdoor temperature that is equaled or exceeded during 99% of hours in a year. In other words, for 99% of the year, the temperature will be higher than this value. So only during the coldest 1% of the year will the temperature be lower. This value is relevant in heating season, aka winter.

How did I make these maps? First, I gathered and organized a massive amount of data from various sources, then used Python to analyze the data, then Folium to create interactive maps.

This map uses data from ASHRAE’s climatic design conditions from 2021, the latest set, from https://ashrae-meteo.info/v2.0/. It has averages of 30 years of data for over 9,000 locations around the world.