Drivers are urged to exercise caution during their morning commutes as black ice may have reformed in isolated spots on Houston roadways overnight. Drivers should look for any wet surfaces, as they can be icy.

Although temperatures are rising across the Houston area after two days of snow and ice, officials are still urging motorists to exercise caution on the roads.

"It's called 'black ice' because it tends to look like the rest of the pavement on the road, although in reality, it's actually clear," the US Forest Service notes. "Black ice forms without creating bubbles, which allows it to blend in with any surface it forms over. Black ice is dangerous precisely because it's hard to detect."