August weather forecast
Vacaville, CA

August, the last month of the summer in Vacaville, is another tropical month, with temperature in the range of an average high of 90.3°F (32.4°C) and an average low of 57.9°F (14.4°C).

Temperature

In August, Vacaville experiences a barely noticeable shift in meteorological conditions, with average high-temperatures moving from 91°F (32.8°C) in July to a still tropical 90.3°F (32.4°C). A marked drop from daytime peak temperatures to an average low-temperature of 57.9°F (14.4°C) is observed during the nights in August.

Heat index

During August, the heat index is appraised at a torrid 96.8°F (36°C). Special measures are necessary to avoid heat cramps and heat exhaustion. Persistent activity could result in heatstroke.
Heat index's context suggests values are appropriate for shady areas and slight breezes. The presence of direct sunlight can raise the heat index values by up to 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'real feel', melds the effects of warmth and moisture to generate a feeling of heat. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. Keep it in mind, direct sunlight can augment the heat you experience, possibly pushing the heat index up by 15 Fahrenheit (8 Celsius) degrees. Heat index values are of high significance for children. Kids often lack the knowledge about the necessity to take breaks and consume liquids. Thirst, as a late symptom of dehydration, necessitates the maintenance of hydration, particularly during enduring physical activities.
To prevent overheating and help regulate its internal temperature, the human body sweat and rely on the evaporation to cool down. When there is an excess of moisture in the atmosphere, the efficiency of the evaporation process is lessened, leading to less efficient body cooling and a sensation of overheating. When body temperature rises due to excess heat gain beyond its removal capability, one might experience heat-related disorders.

Humidity

In Vacaville, the average relative humidity in August is 53%.

Rainfall

The months with the least rainfall are July through September Rain falls for 1 days and accumulates 0.04" (1mm) of rain.

Daylight

The average length of the day in August is 13h and 36min.
On the first day of August in Vacaville, sunrise is at 6:10 am and sunset at 8:17 pm. On the last day of the month, sunrise is at 6:37 am and sunset at 7:38 pm PDT.

Sunshine

In August, the average sunshine in Vacaville is 11.9h.

UV index

June through August, with an average maximum UV index of 6, are months with the highest UV index. A UV Index estimate of 6 to 7 represents a high health risk from unsafe exposure to UV radiation for average individuals.
Note: A daily high UV index of 6 in August leads to these guidelines:
Prevent overexposure. Protection from the sun's harmful effects is needed. Avoid direct Sun exposure and stay in the shade between 10 a.m. and 4 p.m., a time when UV radiation is most intense, noting that not all shade structures offer full protection. A wide-brimmed hat is a staple for defending the face, eyes, ears, and neck from the Sun.