The honest answer is that shade helps a lot, but it does not guarantee a cool seat. A street bench in the shade will generally feel closer to air temperature than one in direct sun, because shade removes direct solar radiation. That is the main thing that makes outdoor surfaces painfully hot. However, if a bench has been baking in the sun for hours and then becomes shaded, it can stay warm for a surprisingly long time because the material has already stored heat. So the real question is not just whether the bench is in shade now, but what it is made of, what color it is, and how long it has been shaded.
Metal benches are a special case. Steel, aluminum, and iron have high thermal conductivity, meaning they transfer heat quickly. In direct sun, they feel scorching because they dump heat into your skin fast. Once they move into shade, they also lose heat to the air faster than wood or plastic, so a shaded metal bench can become touchable sooner. But if the shade just arrived, that metal bench may still feel hot. Aluminum often feels slightly less brutal than dark steel because it reflects more radiant heat, but the finish and paint color matter a great deal.
Wood benches tend to be the most forgiving. Wood has lower thermal conductivity and lower density than metal, so it does not transfer heat into your hand as aggressively. A wooden bench that has been shaded since morning often feels neutral or even genuinely cool. Light natural wood stays cooler than dark-stained wood because lighter colors reflect more sunlight and absorb less heat. Even so, a wood bench that was exposed to afternoon sun can hold noticeable warmth for a while after shade covers it.
Plastic, recycled composite, and concrete behave differently. Dark plastic or composite can absorb a lot of heat and retain it, especially if the material is thick. Concrete and stone have high thermal mass, which means they warm up slowly but hold heat long after the sun goes away. A shaded concrete bench can feel cool in the morning, yet it may still feel warm in the evening if it was exposed during the afternoon.
The type of shade also matters. Shade under a tree with good airflow tends to feel cooler because the tree blocks solar radiation and cools the surrounding air through transpiration. A bench beside a hot brick wall or over dark pavement may still feel warm because nearby surfaces radiate heat. A bench under an open-sided awning cools faster in a breeze than one inside a glass shelter that traps hot air.
So if you are wondering whether a particular street bench will be cool to the touch, look at three things: material, color, and timing. A light-colored wooden bench that has been shaded for hours is your best bet for a genuinely cool seat. A dark metal or dark composite bench that only recently became shaded may look safe but still feel hot. In hot weather, it is always smart to test the surface with the back of your hand before sitting, because shade does not instantly erase stored heat.