What environmental conditions should be avoided when painting outdoors?

High winds and rain can significantly affect the quality and durability of an outdoor paint job. When it is raining, the moisture can prevent paint from adhering properly, leading to issues such as peeling and blistering once the paint dries. Additionally, rain can wash away fresh paint, ruining the finish. High winds can pose challenges as well, as they can cause overspray, leading to uneven application, and they may disturb the drying process. For these reasons, outdoor painting should be avoided under conditions of rain and high winds to ensure a smooth and long-lasting finish.

The other conditions mentioned may have their own drawbacks, but they do not pose as immediate and critical risks to the painting process as rain and high winds do. For example, sunny days might cause rapid drying of paint, which could lead to issues, but it's generally more controllable than the effects of rain.