Severe Weather Warning for Prague and Large Parts of Bohemia

The Czech Hydrometeorological Institute has issued a severe weather warning for Friday, 21 August. A flood alert has also been declared for Prague and northern Bohemia.

Strong to very strong thunderstorms are expected across large parts of Bohemia late on Friday afternoon, during the evening and in the first half of the night into Saturday. The western parts of the region are likely to be spared. The storms will move across the country from the south-west.

The greatest danger will come from torrential rain. Around 40 millimetres of rain could fall locally within a short period. As the thunderstorms will then partly develop into prolonged rainfall, total precipitation of up to 70 millimetres is possible, particularly in central and north-eastern Bohemia.

Meteorologists are also forecasting wind gusts of between 70 and 90 kilometres per hour. Isolated hailstones measuring around two centimetres may also occur.

Flood Risk in Prague and Northern Bohemia

On Friday evening and during the night into Saturday, water levels in smaller rivers and streams could temporarily rise significantly. The first flood warning level could be exceeded on smaller tributaries of the lower Vltava in Prague and on waterways in northern Bohemia. In isolated cases, the second warning level may also be reached.

The sharpest rises in water levels are expected in densely built-up areas. Due to the high proportion of sealed surfaces, rainwater can only seep into the ground to a limited extent and therefore flows particularly quickly into waterways.

Lower Rainfall Totals in Moravia and Silesia

Lower overall rainfall totals are expected in Moravia and Silesia. However, thunderstorms could still bring up to 40 millimetres of rain locally. Wind gusts of around 70 kilometres per hour are expected to occur more frequently there during the night. Isolated hailstones measuring up to two centimetres are also possible.