Very warm weather is expected in central Europe, especially Germany in the next days/weeks. During the entire time, it will be sunny (you can read more about the weather for Berlin in the M.I.L.K. Berlin weather forecast if you subscribe to linus.hoeller [at] milk-weather.org)

Tomorrow it will still be quite "cool", actually very nice, with 21°C in wide parts of N Germany.
On Sunday the Western half of Germany will be warmer than the E half, temperatures up to 22°C are to be expected in SW Germany and far N Switzerland.
On Monday the summer will then arrive. In the SW of Germany and in Switzerland, locally 26°C are to be expected. 24°C will be reached in most of Germany and Switzerland, and 23°C in Austria.
On Tuesday it will be really warm. Up to 28°C are to be expected in wide parts of N Germany, in the alps it will be a few °C cooler.
On Wednesday it will be hot. In all of central Europe (DE, AT, CH) the temperatures will reach or exceed 28°C, in N Germany in some regions over 30°C.
On Thursday it will be even hotter. In most of N and central Germany, temperatures will reach or exceed 30, partly 31°C, in the rest 30 will be nearly or completely reached and similar conditions are expected in the alps.
On Friday it will not be extremely hot, but in most of Germany, a summer day is still to be expected, and in Austria 30°C will be nearly reached again.