• D – temperature of the warmest month is higher than or equal to 10 °C and temperature of the coldest month is less than or equal to -3 °C.
• f – precipitation is relatively evenly distributed throughout the year.
• b - temperature of each of the four warmest months is higher than 10°C, but the temperature of the warmest month is less than 22 °C

In general it can be said that the D climate type can only be found in the Northern Hemisphere, northwards from the C climate zones, closer to the North Pole. The average temperature during the warmest month is higher than or equal to 10 °C, but in the winter the coldest month has an average value of less than -3 °C. In the winter it often snows and it tends to be quite windy and cold due to the polar and Arctic air masses.

Just like the Dfa type, precipitation is evenly distributed throughout the year. In comparison to the Dfa however, summer is slightly colder and the warmest month does not have average temperature above 22 °C. The highest summer temperatures are still usually between 30 and 35 °C, in the winter it drops to -10 to -35 °C.

Precipitation is higher in the summer, but the difference is not very large. Most of the precipitation in the summer occurs during thunderstorms and so quite often there are longer dry periods between them.

This Dfb category includes for example parts of Northern U.S. (for example Buffalo or Calgary), Southern part of Canada (for example Ottawa), Southern part of Russia (for example Vladivostok), Western part of Central Europe or Southern part of Scandinavia (for example Helsinki).