How Weather Affects Your Car A/C

Blue car fast drive on wet road in rain at daytime

The manner in which weather affects car A/C will depend on the type and severity. High temperatures may force the air conditioning to work harder which places strain on the system, while high humidity has similar effects. Understanding how local weather conditions affect your vehicle will enable you to plan accordingly.


Anyone who drives a vehicle in the desert, tropical or subtropical climates is susceptible to extreme heat and air filter clogging due to dust and debris. The reason is that air conditioning units function by transforming their refrigerant gas so it becomes liquid which then cools down the vehicle’s interior. However, if the surrounding temperatures are sweltering, the gas can overheat, which makes it more challenging for the A/C to do its job. Additionally, the air conditioning will also have to use extra refrigerant which means you’ll spend more time and money recharging it. This may also reduce its service life which is why those that use air conditioning in hot climates often have more mechanical issues than those residing in temperate climates.


Those that drive vehicles in northern climates where the winters can be cold and bitter have their own issues to deal with. This may sound odd at first since most drivers do not use their air conditioning at all during winter, but that is the point. When an automobile’s air conditioning is not used for months at a time, dust, bacteria and mildew can start to accumulate within the system.

This is why some drivers who turn on their A/C in late spring or early summer, after not using it for months, are surprised at the unpleasant mildew they encounter.  But aside from that, when an A/C remains inactive for months its internal components may corrode which could lead to mechanical malfunction. This is why experts recommend turning on your A/C periodically during winter and letting a run for a few minutes.


An environment high in humidity tends to have lots of moisture in the air, and is a mainstay of both tropical and subtropical climates. Remember that air conditioning systems function partly by extracting external air to cool down the vehicle’s interior. However, when the humidity is excessive, the A/C will first have to eliminate the moisture from air prior to circulating it inside the system. This in turn may cause stress within the A/C and can inhibit its ability to adequately cool down the vehicle. This is why drivers operating their vehicles in high humidity climates often complain of warm air being emitted from the vents.

How to Stop Weather from Adversely Impacting Your Vehicle’s A/C

While there isn’t much that can be done to change the weather itself, there are a number of steps you can take to minimize the temperature-related damage to your vehicle. For instance, those operating their vehicle in hot weather will want to check their refrigerant levels more often than usual. While experts generally recommend inspecting it every six months, those living in the desert, tropical or subtropical climates should review it every three months. Another tip is to roll down the windows of your vehicle and let it cool down naturally before driving it and turning on the A/C.