As the temperatures warm into the first weekend of May — with the warmest days of the year Sunday and Monday — the threat of “cold water shock” faces anyone who is on the water, whether it be the lakes, the rivers, the ocean, or inland waters.
The high temperatures will be in the 70s and 80s for most of the area late in the weekend into Monday. These temperatures aren’t unheard of for this time of year (the average first 80° in Seattle is May 20), but the waters have only started to warm slightly from their winter chill.
The water temperature of Puget Sound, the inland waters and Strait of Juan de Fuca, and the coast don’t warm all that much during the year anyway -- topping out in the 50s. But the lakes and rivers that so many people play in during the summer months are just as cold!
The human body loses heat about 25 times faster in water than in air, so if you fall into the chilly waters, the chill will take you over very quickly!
The first response that causes problems immediately for many who fall into the water is an involuntary “gasp” of air due to the shock of entering the frigid water. You can possibly inhale water instead of air and then struggle to cough or breathe while attempting to stay afloat.
To prevent this initial critical response from becoming a sudden tragedy, make sure everyone on or near the water is wearing a personal floatation device, and never allow children to play unsupervised near the water’s edge.
Following the initial shock, cold water quickly causes a loss of dexterity as blood is rushed from the hands and feet to keep the internal organs warm. This is the body’s way of self-preservation, but losing the ability to effectively use hands, arms, legs, and feet can cause people to go under. Another great reason to wear a life jacket!
Hypothermia and loss of consciousness take more time depending on the water temperature but could take up to an hour. Still, if someone falls in and is afloat but cannot be rescued safely, call 911 immediately.
While the warmest temperatures of this stretch look to come Sunday and Monday, it will remain warm through next week, and the outlook for May is for a better chance of warmer temperatures than normal. However, like it takes time for a pot of water on a stove to start boiling, it takes many weeks of warmer temperatures for our rivers and lakes to warm too (and rivers fed by snowmelt and lakes fed by glacial runoff stay chilly well through summer.)
We’ll be watching the prospects for record highs in the coming days on KIRO 7. The first record to fall will likely be the 77° daily record high for Seattle Sunday, set on that date in 1992.
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