Prague in summer
Summers in Prague are normally very agreeable with blue skies and sunshine and an average temperature of 17°C (62°F), with an average high of 24°C (75°F) and an average low of 12°C (53°F); therefore, even in summer the nights are cool and it is necessary to pack a jacket. This said, in 2007, temperatures reached 40°C (104°F) with high humidity during July and August, making visiting the city exhausting.
Generally, there is little rain in Prague, but it can rain quite heavily during spring and summer.
Prague in spring and autumn
Spring and autumn are the best times to visit Prague so, we recommend going in May or June, when the temperatures are mild and the days are longer. Be that as it may, don’t forget to bring a waterproof jacket as there are numerous thunderstorms during this period. In autumn, we suggest going no later than October, when the average temperatures are between 8°C (46°F) and 13°C (55°F).
Prague in winter
We don’t recommend visiting the Czech Republic’s capital in winter, especially for those who aren’t keen on cold weather. The average lows are -3°C (26°F) and the average highs are 1°C (33°F) or 2°C (35°F). Moreover, these months are very dark, which makes visiting the city dreary and much less appealing. On a positive note, Prague is breath-taking when it snows and the Vltava River is frozen over.