Bohemia, to the west, consists of a basin drained by the Elbe (Czech: Labe) and the Vltava rivers, surrounded by mostly low mountains, such as the Krkonoše range of the Sudetes. The highest point in the country, Sněžka at 1,603 m (5,259 ft), is located here. Moravia, the eastern part of the country, is also hilly. It is drained mainly by the Morava River, but it also contains the source of the Oder River (Czech: Odra).
Water from the Czech Republic flows to three different seas: the North Sea, Baltic Sea and Black Sea. The Czech Republic also leases the Moldauhafen, a 30,000-square-meter (7.4-acre) lot in the middle of the Hamburg Docks, which was awarded to Czechoslovakia by Article 363 of the Treaty of Versailles, to allow the landlocked country a place where goods transported down river could be transferred to seagoing ships. The territory reverts to Germany in 2028.
Phytogeographically, the Czech Republic belongs to the Central European province of the Circumboreal Region, within the Boreal Kingdom. According to the World Wide Fund for Nature, the territory of the Czech Republic can be subdivided into four ecoregions: the Western European broadleaf forests, Central European mixed forests, Pannonian mixed forests, and Carpathian montane conifer forests.
There are four national parks in the Czech Republic. The oldest is Krkonoše National Park (Biosphere Reserve), and the others are Šumava National Park (Biosphere Reserve), Podyjí National Park, Bohemian Switzerland.
The three historical lands of the Czech Republic (formerly some countries of the Bohemian Crown) correspond with the river basins of the Elbe (Czech: Labe) and the Vltava basin for Bohemia, the Morava one for Moravia, and the Oder river basin for Czech Silesia (in terms of the Czech territory).
The Czech Republic mostly has a temperate oceanic climate, with warm summers and cold, cloudy and snowy winters. The temperature difference between summer and winter is due to the landlocked geographical position.
Temperatures vary depending on the elevation. In general, at higher altitudes, the temperatures decrease and precipitation increases. The wettest area in the Czech Republic is found around Bílý Potok in Jizera Mountains and the driest region is the Louny District to the northwest of Prague. Another factor is the distribution of the mountains.
At the highest peak of Sněžka (1,603 m or 5,259 ft), the average temperature is −0.4 °C (31 °F), whereas in the lowlands of the South Moravian Region, the average temperature is as high as 10 °C (50 °F). The country's capital, Prague, has a similar average temperature, although this is influenced by urban factors.
The coldest month is usually January, followed by February and December. During these months, there is snow in the mountains and sometimes in the cities and lowlands. During March, April, and May, the temperature usually increases, especially during April, when the temperature and weather tends to vary during the day. Spring is also characterized by higher water levels in the rivers, due to melting snow with occasional flooding.
The warmest month of the year is July, followed by August and June. On average, summer temperatures are about 20–30 °C (36–54 °F) higher than during winter. Summer is also characterized by rain and storms.
Autumn generally begins in September, which is still warm and dry. During October, temperatures usually fall below 15 °C (59 °F) or 10 °C (50 °F) and deciduous trees begin to shed their leaves. By the end of November, temperatures usually range around the freezing point.