Hot air originating from Africa will begin to flow into the Czech Republic on the back side of the high pressure area over Central Europe. The heat will peak at the weekend, with afternoon highs reaching between 35 and 40°C. Such temperatures are already extreme and it is likely that the absolute record of 40.4 °C from August 2012 will be surpassed. There is some hope for a change on Monday, when a significant cold front with numerous thunderstorms, showers and rain should cross the Czech Republic from the west. In the influx of cooler air from the northwest, the afternoon temperatures on Tuesday should be around 25 to 27 °C. Numerical models are still in disagreement about how big the cooling will be, and the forecast will continue to be refined. The hot weather will tempt you to swim – the water temperature in the natural reservoirs and dams is now between 24 and 26 °C. Clear to partly cloudy will prevail on Thursday. We will measure 18 to 14 °C in the morning, around 11 °C in the valleys and around the rivers. Maximums will reach 29 to 34 °C. There will be a weak northeast wind up to 4 m/s. It will be mostly clear to partly cloudy on Friday. Night temperatures will drop to 20 to 15 °C, in the northeast to 13 °C. Afternoon temperatures will rise to 31 to 36 °C. There will be a light wind from the east up to 4 m/s. On Saturday we expect almost clear to partly clear, extremely warm. The morning lows will drop to 21 to 16 °C, in the northeast to 14 °C – in several places we will also experience a so-called tropical night. In the afternoon it warms up to 34 to 38 °C. There will be a weak southeast wind up to 4 m/s. Sunday will be clear or almost clear, extremely warm. In Bohemia, the first showers or thunderstorms will occasionally form later in the afternoon and evening. Morning minimum temperatures will drop to 23 to 19°C, in larger cities and higher ground with light southerly winds it may be around 25°C – a tropical night in many places. The highest daily temperatures will rise to 35 to 40 °C. There will be a moderate wind from the south with a speed of 2 to 5 m/s. During Monday, a cold front will cross the Czech Republic from the west, it will gradually become cloudy to overcast with showers and thunderstorms. While in the Czech Republic it will cool down to 25 to 29 °C, in Moravia and Silesia the temperatures can still rise to 39 °C. From Tuesday, it will cool down in the whole of the Czech Republic to temperatures of around 26 °C.