With the season's first stretch of triple-digit afternoons having arrived in California's Central Valley, agencies are warning growers and others who work outside to take precautions against the heat.

As Tuesday's highs were slated to top out at 108 in Bakersfield, 106 in Fresno and 105 in Redding, the National Weather Service is urging people outside to drink lots of water, wear light-colored clothing and avoid being out during the hottest times of the day.

Meanwhile, California's Division of Occupational Safety and Health reminds employers with outdoor workers that state regulations require them to take the following four steps to prevent heat illness:

For more information from Cal/OSHA on preventing Heat Illness, click here.

 While some communities saw their first triple-digit days of 2019 last week, the season's first prolonged heat spell began Monday, with Fresno reaching 103, Bakersfield climbing to 104 and Sacramento topping out at 100, according to the weather service.

The heat illness warnings come as harvests are ongoing for numerous crops, including Valencia and navel oranges, lemons, Star Ruby grapefruit, zucchini, squash, cucumbers, tomatoes and eggplant, according to the National Agricultural Statistics Service's weekly crop progress report.

Other field work is also underway, as growers are applying nutrient sprays and pesticides, herbicides and fungicides to orchards and vineyards; thinning and positioning shoots in vineyards, cutting hay, repairing irrigation lines and mowing orchard floors, NASS reports.

Temperatures are expected to cool slightly later in the week, peaking in the low 100s in the Sacramento Valley and high 90s in the San Joaquin Valley through the weekend, the weather service predicts. However, the federal Climate Prediction Center foresees a strong chance of above-average temperatures throughout the West this summer.