There are normally 1 hour of bright sunshine each day in Lima in August - that's 11% of daylight hours. Daily low temperatures are around 59°F, rarely falling below 57°F or exceeding 62°F. What's the Weather like in Lima in August Temperature August in Lima , Peru is statistically the coolest month of the year with an average temperature of 17°C with a high of 19°C and a low of 15°C. Daily high temperatures are around 67°F, rarely falling below 63°F or exceeding 70°F. How warm is the sea around Lima in August? The lowest daily average high temperature is 66°F on August 8. Get the monthly weather forecast for Lima, Lima, Peru, including daily high/low, historical averages, to help you plan ahead. Average Weather in August in Lima Peru. The lowest daily average low temperature is 59°F on August 22. The average sea temperature around Lima in August is 17°C .