Humid continental climate facts for kids

A humid continental climate is a type of weather pattern found in certain parts of the world. It was first described by a scientist named Wladimir Köppen in 1900. This climate is special because it has four clear seasons. You'll experience big changes in temperature throughout the year. Summers are usually warm to hot and often humid. Winters are cold, sometimes very cold, and snowy.

Rain and snow usually fall throughout the year. However, some areas might have drier periods. To be called a humid continental climate, the average temperature of the coldest month must be below 0°C (32°F) or -3°C (27°F). Also, at least four months must have an average temperature of 10°C (50°F) or higher. This climate is not found in very dry places like deserts.

You'll mostly find humid continental climates between 40°N and 60°N latitude. This includes central and northeastern parts of North America, Europe, and Asia. It's very rare in the Southern Hemisphere. This is because there's more ocean and less land there, which makes the climate milder.

Some areas, like parts of Hokkaido in Japan or Nova Scotia in Canada, are close to the sea. They have cooler summers and lots of snow. Their winters are just below freezing. More inland areas, like in northeast China or southern Siberia, have "hyper-continental" climates. These places have very cold, dry winters, but their summers are longer and warmer.

Other regions, such as parts of Honshu in Japan or the Midwestern United States, have a more moderate version. They have hotter, more humid summers and moderately cold winters with some snow.

What Defines This Climate?

The snowy city of Sapporo, Japan, has a humid continental climate (Köppen Dfa).

Scientists use the Köppen climate classification system to define this climate. For a place to have a humid continental climate, two main things must be true:

• The average temperature of its coldest month must be below 0°C (32°F) or -3°C (27°F).
• At least four months must have an average temperature of 10°C (50°F) or higher.

These temperature rules are important. The -3°C line in Europe often marks where winter snow stays on the ground. The 10°C average temperature is usually the minimum needed for trees to grow and reproduce. This climate zone often has a wide range of temperatures between summer and winter.

The second letter in the climate code tells us about rainfall:

• s: Means a dry summer. The driest month in summer has very little rain.
• w: Means a dry winter. The driest month in winter has much less rain than the wettest summer month.
• f: Means no dry season. Rain and humidity are often high all year.

The third letter describes how hot the summer gets:

• a: Means a hot summer. The warmest month averages at least 22°C (71.6°F).
• b: Means a warm summer. The warmest month averages below 22°C (71.6°F). But at least four months are above 10°C (50°F).

Rain and Snow

In North America, moisture for this climate comes from the Great Lakes, the Gulf of Mexico, and the Atlantic Ocean. Many areas get rain and snow fairly evenly throughout the year (f type). Other places might have less snow in winter, which can lead to a winter drought (w type).

Snowfall happens in all humid continental climates. In many places, snow is more common than rain during the coldest part of winter. If there's enough winter precipitation, the snow can pile up deep. Most summer rain comes from thunderstorms. Sometimes, in North America and Asia, even a tropical cyclone can bring rain. The "humid" part of the name means the climate isn't dry enough to be a semi-arid climate or desert climate.

Plants and Trees

Mixed forest in Vermont during autumn

Forests grow well in this climate. You can find different types of forests here. These include temperate woodlands, grasslands, deciduous forests (trees that lose leaves), evergreen forests, and coniferous forests (trees with needles). In wetter areas, you might see maple, spruce, pine, fir, and oak trees. The changing colors of leaves in autumn are a beautiful sight in deciduous forests.

Nearby Climates

As you move towards the poles (north or south), these climates change into subarctic climates. These have short summers and very cold winters, where only conifer trees grow. Moving towards the equator, hot-summer continental climates blend into humid subtropical climates. Warm-summer continental climates often transition into oceanic climates. Both of these have milder winters, where temperatures stay above 0°C (or -3°C). Some continental climates with less rain become semi-arid climates. They have similar temperatures but much less precipitation.

Hot Summer Continental Climate

Regions with hot-summer humid continental climates

A hot summer continental climate means the warmest month has an average temperature of at least 22°C (71.6°F). Since these climates are mostly in the Northern Hemisphere, the warmest month is usually July or August. High temperatures in summer often reach the high 20s to low 30s °C (80s °F). In contrast, average January afternoon temperatures are usually below freezing. The period without frost typically lasts 4 to 7 months.

In North America, this climate is found in parts of the central and eastern United States. This stretches from west of 100°W longitude to south of about 44°N latitude, all the way to the Atlantic Ocean. As you go eastward, there's more rain. Some western states also fit the temperature rules but are very dry.

In the eastern and Midwestern United States, states like Iowa, Ohio, Illinois, and parts of New York have this climate. In Canada, only parts of Southern Ontario and the city of Montreal experience it.

In the Eastern Hemisphere, you find this climate in inland Eurasia and east-central Asia. In Europe, it's near the Black Sea in southern Ukraine, southern Russia, and parts of Romania and Bulgaria. These areas can be drier. In East Asia, this climate often has a monsoon season, meaning much more rain in summer than in winter. Winters are very cold due to the strong Siberian High pressure system.

A version with dry winters and monsoonal summer rain is found in northern China, parts of Russia, and the Korean Peninsula. This is called the Dwa climate. Dsa climates are rare. They are usually in high mountain areas next to Mediterranean climates. These places have hot summers and cold winters.

This hot summer climate type does not exist in the Southern Hemisphere. The continents there don't extend far enough south, or they are too narrow. Also, the strong ocean influences around 40°S prevent these climates from forming.

Warm Summer Continental Climate

Regions with warm-summer humid continental climates

This type of continental climate is also called a hemiboreal climate. Here, the average temperature in the warmest month is below 22°C (71.6°F). Summer daytime temperatures usually range from 21°C to 28°C (70-82°F). The average temperatures in the coldest month are well below 0°C (32°F) or -3°C (27°F). The frost-free period typically lasts 3 to 5 months. Very hot weather lasting more than a week is uncommon.

The warm summer continental climate covers a larger area than the hot summer type. In North America, it stretches from about 42°N to 50°N latitude. This includes parts of Southern Ontario, southern Quebec, and the northern United States. You can also find it further north in Canada and in the high Appalachian Mountains. In Europe, this climate reaches its most northern point in Bodø, Norway, at 67°N.

High-altitude places like Flagstaff, Arizona in the western United States also have Dfb climates. Some areas in the Canadian Prairie Provinces fit the temperature profile but are too dry.

In Europe, this climate is found in much of Central Europe, including parts of Germany, Austria, Poland, and Hungary. It's also common in Eastern Europe, like Ukraine, Belarus, and central Russia. The southern and central parts of the Nordic countries and the Baltic States also have this climate. These areas have mild summers, long cold winters, and less rain than the hot summer type. However, short periods of extreme heat can still happen. Northern Japan has a similar climate.

In Asia, this climate is in northern Kazakhstan, southern Siberia, parts of Mongolia, and northern China. These climates are usually dry and very cold in winter due to the Siberian High. But their summers are warm and long enough to avoid being classified as subarctic.

In the Southern Hemisphere, this climate is rare. It exists in specific areas like the Southern Alps of New Zealand and the Andes Mountains in Argentina and Chile.

See also

In Spanish: Clima continental húmedo para niños

• Continental climate
• Subarctic climate
• Hemiboreal