Update: Dangerous Heat Continues From The Central Valley To The Sierra Nevada
The National Weather Service has issued a Heat Advisory for Yosemite National Park (outside of the Valley floor) until 10 AM Wednesday. The Heat Advisory that is already in effect for the western slope of the northern Sierra Nevada and the Excessive Heat Warning that is in effect for the Mother Lode, have both been extended until 8 PM Friday. Finally, the Excessive Heat Warning now in effect for Mariposa County, the Yosemite National Park Valley floor, and the central San Joaquin Valley, has been extended until 10 AM Saturday.
High temperatures are 15 to 20 degrees above normal. This is creating dangerously hot conditions, with high temperatures ranging from 105 to 110 degrees, depending on your exact location. Widespread areas of Major to Extreme HeatRisk continue to exist.
Such well-above-normal temperatures, even in the high Sierra Nevada, is having a significant impact and making outdoor activities more likely to cause heat-related illnesses than what most folks are used to, even at the upper elevations.
This level of rare, long-duration extreme heat with little to no overnight relief affects everyone, especially those without effective cooling and/or adequate hydration. Heat related illnesses increase significantly during extreme heat events, particularly for those working or participating in outdoor activities.
Take extra precautions when outside. Wear lightweight and loose fitting clothing. Try to limit strenuous activities to early morning or evening. Take action when you see symptoms of heat exhaustion and heat stroke.
To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1.
There will be impacts likely in most health systems, heat-sensitive industries and infrastructure.
Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.
Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes.
There is limited overnight relief with low temperatures ranging from the 70s to the lower 80s.
Area waterways will continue to run cold and fast, creating dangerous conditions for those seeking relief in rivers and lakes.
Stay cool, stay hydrated, stay informed.