Why bridges freeze before roads

You've heard you've heard the storm team say it... bridges freeze before roads.

Storm team 10's david siple explains why this happens in the winter.

You should always drive with caution when temperatures are below 32 degrees.

That is especially important when you cross a bridge.

Before you cross most bridges with a creek or a river below it, you'll likely see this sign before a bridge.

So why can bridges be so dangerous during the cold months?

Water beneath cold months?

Water beneath the bridge, that isn't frozen, is obviously above 32 degrees.

Overnight low air temperatures this time of year is around 23 degrees.

The creek or river water can evaporate when the surrounding air is warmer than the water.

That evaporated water will rise and, under the right conditions, stick to surfaces that are below freezing.

Like the roadway on the bridge.

This can cause icy conditions on the bridge and can make the road very dangerous.

This is why it is very important to always stay tuned to storm team 10 and drive cautiously in the winter time.

In the wthi studio, i'm storm team 10 meteorologist david siple.

Tonight: rain likely, mainly