All Weather Tires vs. All-Season Tires, is there a difference?
All-season tires are a versatile and practical option to provide safe performance in mild conditions, but not a suitable option for driving in severe snow conditions. All-weather tires are designed with an open tread pattern (great for deep snow), a high number of minute slits in the tread blocks to give better control and handling on wet surfaces, and a special rubber compound to match the environment.
All-weather tires give the best performance in mild winter conditions with temperatures above and below 7° C including fast-melting snow and rain. This type of tire is one of the newest on the market and built to operate in the variable winter climates. All-weather tires are different to traditional winter tires because they are built to handle well in both warm and cold climate conditions, and can be left on the car year-round if preferred. But, this tire has tread compound that isn’t nearly as soft as the winter tires (but still softer than all-season), so not a practical choice to use in severe snow or cold temperatures. It is possible to identify the all-weather tire by noting the three-peaked mountain and snowflake on the tire sidewall.
All-season tires give the most desirable performance in the mild, slightly wet, muddy, and dry conditions. This type of tire isn’t a practical choice for most severe weather conditions, but is still more effective in snow and ice than summer tires because of the better traction performance. All-season tires have a unique tread design and shape to improve on-road performance year-round. While these tires can generally provide the desired traction in light snow, they aren’t the type of tire that you want on the car in a blizzard. The hard compound of these tires means they aren't in a position to give the desired traction once the temperature starts to drop below 7° C. It is possible to identify the all-season tires by reading the Mud and Snow (M+S) mark on the tire sidewall.
What is the acceptable tread depth?
Provided the tread depth on either of these tires is at least 3.5 mm then they are acceptable to use on the highways that have winter tire requirements in place (October-March). For ease of measuring the tread depth, a simple tire depth gauge can be purchased from a local auto supplies store or a garage at low-cost. Overall, if you only plan to drive in mild temperature conditions that get regular rainfall instead of snow, you are certain to find the all-season or all-weather tires are a practical and safe option. But, for those living and driving at regular intervals in cold weather with slush, snow, and ice, it benefits to upgrade and install the winter tires with the mountain snowflake symbol which is essential to give the better on-road handling and performance.