The main reason that all-season tires perform better than all-weather tires in the summer is the same reason why all-weather tires perform better than all-season tires in the winter. The reason all-weather tires perform so well in the winter on snow and ice is due to their more aggressive tread patterns and tread compounds that allow for use in colder weather. All-season tires handle better in the summer than all-weather tires, as their tread patterns are less aggressive and allow for more contact with the road. Also, the rubber compound can withstand a greater temperature range.
This allows all-season tires to be ideal for spring and summer with their unique tread design that allows them to have excellent handling and stability on wet and dry payment alike. If you come from a place where summers get extremely hot there is no need to worry, as all-season tires are made to handle a large range of temperatures.
If you live in an area where there are severe winters and you are set on not changing into dedicated winter tires, then your best choice would be to invest in all-weather tires to avoid changing tires in the winter. There are many high-quality all-weather tires, like the Nokian WR G4. Nokian WR G4 all-weather tires offer excellent functionality in varying weather conditions, remaining stable and easy to control even at high speeds while remaining fuel-efficient and environmentally friendly due to their low rolling resistance.
Even though all-weather tires are not ideal for summer driving, they remain the best choice if the idea is to keep one set of tires throughout the year in an area with harsh winters. If this is not the case, then your best choice would be to look for an all-season tire that offers excellent handling and stability, like the Nokian zLine.
The choice between all-season and all-weather tires depends on where you live and what kind of driving you do. If you live in an area that does not experience a true winter season, you would be able to drive with all-season tires year-round and avoid changing tires. If you experience winter weather where you live, your best option is to invest in all-season tires from spring to fall and change into winter tires in the winter.