Why is it still so hot inside the car when it rains in summer?

[OKai]

In summer, the car gets hot when it rains because heat enters the air along with water vapor, causing the temperature to rise. When it reaches a certain level compared to human body temperature, people feel stuffy in the hot and humid air. Solutions: You can turn on the car's air conditioning to lower the temperature, or open the windows for ventilation to dissipate the heat. Defogging process: If you want to completely eliminate fog inside the car, you should choose to turn on the air conditioning and select hot air to blow onto the windshield. Similarly, first use the external circulation mode, select hot air and the front windshield outlet, wait for about 5 minutes, then switch to internal circulation or simply turn it off. Of course, if the air conditioning has a heating function, the defogging effect will be faster and better.

[ArianaFitz]

To be honest, the heat inside the car on rainy summer days is mainly caused by humidity. Rain makes the air damp, and with high humidity, heat becomes harder to dissipate, making it feel stuffier than on sunny days. The car's metal body absorbs a lot of heat during the day, and when it rains, the evaporation of rainwater absorbs heat. However, the small interior space accumulates a lot of heat, and with the windows closed preventing airflow, it turns into a big steamer. I often encounter this situation while driving—even after the rain stops, I still end up sweating buckets when I get in the car. Additionally, rainwater may block the air conditioning intake or affect the car's heat dissipation, reducing the cooling effect. It's recommended to turn on the air conditioning in dehumidification mode in advance or briefly open the doors to let some air in and alleviate the discomfort. In short, humidity combined with a confined space is the main culprit.

[BellaRose]

I often drive in the summer and find that rainy days make the car interior even more unbearable. When humidity rises, the air conditioning has to work harder to dehumidify before it can lower the temperature. Otherwise, the air becomes sticky, and the body's sweat doesn't evaporate quickly enough to dissipate heat. Sometimes, raindrops come in, and when I close the windows, the lack of ventilation makes it even harder to release the heat. I remember once driving in light rain, and the heat inside the car made me gasp for breath. Later, I checked and found that the clogged air filter was trapping even more moisture. Rainwater also affects the car's surface heat dissipation, making it harder to lower the interior temperature. Experience suggests using the recirculation mode in such situations to avoid outside humidity from entering and to keep the air conditioning clean. If the rain is heavy, using a sunshade or car cover before parking can help prevent heat buildup. For safety, don't push through the stuffy heat while driving.

[JourneyFitz]

The car gets extremely hot after summer rains, placing significant strain on the body. High humidity causes the perceived temperature to rise sharply, while slowed sweat evaporation increases heatstroke risks. The main reason heat lingers in cars is rainwater increasing air moisture, which hampers heat dissipation. Closed windows trap heat like a greenhouse. Turning on the AC for dehumidification or briefly ventilating beforehand is essential. Health comes first—never overlook this.

[MaverickMarie]

From the perspective of the car's internal systems, there are several reasons why the interior gets hot during summer rains. The air conditioning efficiency decreases in humid conditions, as the compressor works harder to dehumidify, consuming more energy with poorer results. If set to external circulation, moisture enters the cabin, exacerbating the stuffiness. Rainwater may seep into electrical circuits or cooling devices, affecting cooling performance. Regular maintenance of the air filter and ensuring the system is unobstructed can improve the situation. Choosing internal circulation mode with appropriate fan speed allows smoother air circulation inside the car, stabilizing the temperature faster. Avoid parking for long periods in enclosed environments during rainy days, and simple checks can prevent malfunctions.

[StChristian]

Environmental factors cause the car to become hot on rainy days. In summer, the air is already warm, and when rain falls on the hot ground, steam rises, enveloping the entire car body with unusually heavy humidity. Dark-colored car bodies absorb heat more easily, and closed windows act like a greenhouse, trapping heat for a long time. Parking in a spot facing the sun can make the car feel like a heater after the rain. I once experienced driving home on a rainy day, where the lack of ventilation made the car stiflingly hot. Later, using a light-colored car cover improved the situation. Understanding these mechanisms can help effectively address the issue, such as opening windows for ventilation or turning on the air conditioning in dehumidification mode in advance to prevent the problem from worsening and affecting comfort.