RICHMOND, Va. -- As Central Virginia sees temps in the 70s and possibly near 80 next week, folks will likely be headed out on the James River.
"It is one of my favorite places when the weather warms up to come down here," WTVR CBS 6 Chief Meteorologist Zach Daniel said. "There's so much to do. It's such an urban playground, this James River."
But while the air temperature may be warming, the water in the river remains very cold.
"There's a lag time there because of something called specific heat. The air cools at night and warms up quickly during the day. But the water temperature — it takes weeks on end for that to warm up," Daniel explained. "And so that creates a danger called cold water shock if you happen to find yourself immersed in water."
Cold water shock happens when you get into the water and experience involuntary gasping where you could ingest water, possibly choke, hyperventilate or even drown.
"It causes your heart rate to rapidly beat and your blood pressure to increase. And then when you get into water like that you start to panic and you can't make good decisions," Daniel said.
That is why a personal flotation device if always recommended if you are you are going out on the water — especially when it is cold.
Daniel outlined the 120 rule, which is the air and water temperatures added together. On Wednesday evening it was 68 degrees and the water in the James was 46 degrees, which equals 114.
"That is lower than 120, so it is a dangerous switch situation for today," Daniel said. "You want it to be over 120."