Heat advisory issued for Sonoma County amid triple-digit temps

Santa Rosa is in for its third straight day of triple-digit temperatures Thursday, prompting National Weather Service, public health and law enforcement recommendations for avoiding heat-related illnesses and misfortune.

The heat wave, locally, could extend to four consecutive days if forecast highs by AccuWeather of 100 Thursday and again Friday prove accurate, with temperatures moderating to 90 on Saturday and 87 Sunday.

Santa Rosa recorded a sizzling 102 on Wednesday, a sequel to Tuesday's high of 100, while a dozen other North Bay cities also broke the century mark, led by Healdsburg and Windsor at 105 and Calistoga, Cloverdale, St. Helena and Ukiah at 104 on Wednesday.

Santa Rosa's record high for the date is 107, set in 1944.

Around the state, 19 cities were hotter than 100, with a high of 107 at Livermore and Needles.

The weather service issued a heat advisory for Wednesday and Thursday, warning that inland temperatures around the Bay Area, including Sonoma County, will range from the mid-90s to the low 100s in the afternoon, with cooling during the evening and afternoon hours.

The advisory applies from 11 a.m. to 7 p.m. Thursday.

Overnight temperatures are expected to bring some relief, with 55 tonight and Friday night, 57 Saturday night and 55 Sunday night, according to AccuWeather.

Sonoma County grape growers, about one-third of the way through a relatively light harvest, are picking the fruit mostly at night, which is good for both grapes and workers, said Steve Sangiacomo of Sangiacomo Family Vineyards.

Heat pushes the grapes to maturity and 'gets us really going full steam,' he said.

Grapes can tolerate a couple of heat waves, and since the summer has been mild until this week, Sangiacomo said there is scant damage. Rain poses a lot greater risk to the crop than heat, he said, acknowledging that Californians are longing for a break in the four-year drought.

The Sonoma County Department of Health Services said Wednesday that excessive heat 'poses a significant health risk, particularly to the elderly, young children, pregnant women and those with chronic diseases.'

Heat-related illnesses range from cramps and heat exhaustion to heat stroke and, in extreme cases, even death, Scott Alonso, a department spokesman, said in a press release.

Warning signs of heat-related illness include heavy sweating, muscle cramps, tiredness or dizziness, nausea or vomiting, headache or weakness, he said.

To guard against health problems, the department advised people to drink plenty of cool fluids, avoiding caffeinated or alcoholic beverages, wear lightweight clothing, and to limit physical activity and stay indoors in an air-conditioned space. People who do not have air-conditioning are advised to visit a public space, such as a library, shopping mall or community center.

Outdoor work or strenuous activity should be done in early morning or evening after the temperature cools down.

The California Highway Patrol warned against leaving any child, elderly adult or animal unattended in a vehicle. Temperature can escalate quickly inside a vehicle, even with windows cracked open, potentially causing heat stroke, suffocation and brain damage, the CHP said.

You can reach Staff Writer Guy Kovner at 521-5457 or guy.kovner@pressdemocrat.com. On Twitter @guykovner.