In order to get the most out of your visit to Austria, you should decide when to visit Austria. Because of weather in the country vary depending on when you're visiting Austria. The best time to visit Austria is during April - May and September - October.
Here is the seasonal overview of Austria-
April to May - Spring / Good Season
Make sure you carry rain-proof clothing and an umbrella if you are travelling in April - May.
Avg. Temperature:58 - 65 F / 9 - 15 C
Rain Fall: 40 - 118 mm
June to August - Summer / High Season
The crowd may increase as compared to the previous season, prices go up - they might even double. Since the crowds would be high, it is better to book well in advance.
Avg. Temperature:74 - 76 F / 18 - 19 C
Rain Fall: 88 - 107 mm
September to October - Fall / Good Season
The weather will be extremely pleasant. Since the peak season is over, you don't have to expect too many tourists.
Avg. Temperature:57 - 79 F / 10 - 15 C
Rain Fall: 44 - 64 mm
November to March - Winter / Low Season
This is the off-season for Austria. Winter months in Austria can be quite unique. While crowds are lower and the prices as well much lower. The cost of accommodation would be extremely low, but expect a lot of snow.
Avg. Temperature: 44 - 55 F / -1 - 5 C
Rain Fall: 29 - 99 mm
Above mentioned are the seasons in Austria. Now it's your turn to choose one of them. But, before travelling to Austria make sure you hold a valid Austria visa. If you don't have Austria visa, you can refer to the Austria Visa Guide.
Usually, people visit a country when the tourist season is in full swing. This tourist season is established due to the climate being so good during that time. Austria’s weather and temperatures vary depending on your location in Austria. The eastern side is nice with hot summers and mild winters. The Alpine region is much colder due to the mountains. Like many tourist places, the best tourist season would be right before or after the summer.
Since the summer is very hot, it would not be good to visit Austria then. Therefore, the months that are the best to visit and tour Austria would be in April, May, September and October. If you can’t make those months maybe the month before or after would be good too.