Graz, where it's located

The climate of Graz is moderately continental, with cold winters and warm summers.
Graz is the second Austrian city and capital of Styria, and is located in the south-east of the country, east of the Alps, at an altitude of 350 meters (1,150 feet).
The average temperature of the coldest month (January) is of -0.5 °C (31 °F), that of the warmest month (July) is of 20 °C (68 °F). Here are the average temperatures.
Graz - Average temperatures
Min (°C)-4-315101315141161-2
Max (°C)36111520232525201584
Min (°F)252734415055595752433428
Max (°F)374352596873777768594639

Precipitation amounts to 820 millimeters (32.3 inches) per year: so, it is at an intermediate level. It ranges from 25 mm (1 in) in the driest month (January) to 125 mm (4.9 in) in the wettest (July). The mountains to the west reduce precipitation in winter (because they block the western currents) while increasing it in the summer (because they cause thunderstorms). Here is the average precipitation.
Graz - Average precipitation

On average, there are around 1,890 sunshine hours per year. Here are the average sunshine hours per day.
Graz - Sunshine


Best Time

In order to avoid both the winter cold and the summer heat, the best times to visit Graz are spring and autumn, and in particular, the months of May, June and September: daytime temperatures are pleasant, although it's better to bring a sweater and a jacket for the evening. In July and August, the temperature is usually not too hot, however, there is the risk of some very hot days, which can happen, though more rarely, also in the second half of June and in the first half of September.