August is, by every measure, the hottest month of the year in Lanzarote. Thankfully, Lanzarote does not generally get the same extreme high temperatures as the south of Mainland Spain, but you can still expect at least some days to reach the mid 30s °C in August.
The average daytime maximum temperature in August is 29.1°C, and the lowest daytime high ever recorded in August is 24.4°C! Some days will likely reach the mid-thirties (Celsius), and the highest temperature ever recorded is 43.6°C (6th of August 1980).
The average nightly low temperature in August is 21.2°C, and it doesn’t usually drop below 19°C at all during the month. It can feel even warmer in large resorts such as Puerto del Carmen, so booking a room with Air-conditioning is advisable at this time of year. The lowest nighttime temperature ever recorded at Lanzarote Airport was a freakish 16.6°C back in 1982. Needless to say, you won’t need to pack warm jackets or cardigans if you are visiting in August.
Clear Skies or Cloudy?
Similar to July, August tends to be a very sunny month in Lanzarote, though there is often some cloud out to sea or in the north. On average, there is just one completely overcast day during the whole month. There is often some haze at this time of year, though you’ll need to worry more about sunburn than lack of sunshine.
Though slightly less windy than July (the windiest month), August is still a windy month on the island. If that bothers you, choose a resort on the south coast with good shelter from the wind. The average wind speed is 27.6kmph, and sun seekers should be aware of its cooling effects, since you can become badly sunburnt without realising it.
Though not as warm as the Mediterranean, the sea temperature around Lanzarote starts to become more comfortable during August and hits about 22°C. It can still feel cold on certain beaches around the island, so look for shallow water in the late afternoon for the warmest water.
Aemet.es Weather forecast from the Spanish State Meteorological Agency