San Luis Obispo’s official high temperature of 109 degrees Monday at Cal Poly broke a record for a second straight day, beating the 104 degrees recorded in 1993, according to local weather forecaster John Lindsey.
One volunteer who is part of Lindsey’s network of weather watchers recorded an unofficial 113-degree reading at Sinsheimer Park at 1 p.m.
Paso Robles’ high of 108 degrees — recorded at Paso Robles Municipal Airport — broke a 1963 record of 105, according to Lindsey, a communications specialist for Pacific Gas and Electric Co.
The cause of the scorching temperatures was a high-pressure ridge that strengthened Monday, according Lindsey.
That upper-level ridge is expected to move slightly eastward today, bringing some relief to the coast and coastal valleys, but the North County will remain hot, Lindsey added.
As the ridge moves farther east Wednesday, cooling is expected throughout the area, with the return of the marine layer and fog, Lindsey said.
During the weekend, a weak upper-level trough is expected to cross California, he said. That should bring temperatures that would be near normal for early October, with widespread coastal low clouds and fog along the coast.
On Monday, the dry heat led medics to respond to numerous reports of heat stroke.
Both San Luis Obispo hospitals said they treated two patients each for heat-related symptoms.
French Hospital Medical Center spokeswoman Megan Maloney said the patients were rehydrated and checked for underlying illnesses. The two patients there overheated in their homes, she added.
At Sierra Vista Regional Medical Center, one person was treated for heat exhaustion after riding his bike when it was 110 degrees. Another man was elderly and because dehydrated because he had not consumed enough fluids, hospital spokesman Ron Yukelson said.
The heat wave prompted county officials to issue a public health alert stressing that air conditioning is the No. 1 protection against heat-related illness or death.
The elderly, very young and people with chronic diseases or mental illness are said to be at higher risk, health officials said.
Signs and symptoms of heat-related illness include heavy sweating, paleness, muscle cramps, tiredness, weakness, dizziness, headache, nausea or vomiting and fainting, according to the county Public Health Department alert.
Heat stroke — a life-threatening condition — can take place if the body’s temperature rises above 103 degrees and skin is red, hot and dry with no sweating. Symptoms also include a rapid, strong pulse, a throbbing headache with dizziness, nausea, confusion or unconsciousness, health officials warned.
The health department suggests drinking plenty of nonalcoholic fluids and scheduling outdoor activities for early morning or late evening. Also, use sunscreen and wear light-colored, loose-fitting clothing.