Weather in Reykjavik in August

How August compares

August is the 2nd warmest month of the year in Reykjavik. Against London's average high of 21.4°C in August, Reykjavik is 8.1°C cooler by day and 5.3°C cooler at night.

Daytime and night-time in August

The typical August day in Reykjavik peaks at 13.3°C, but that is an average: the warmest 10% of days reach 16.0°C or more. Roughly 1 in 1000 days top 25°C. Nights average 8.2°C; one night in ten drops to 5.6°C or lower, so pack a layer for evenings - it is genuinely cool after dark. Between 1991 and 2020 the hottest August day here reached 25.1°C (2004-08-11) and the coldest night 2.6°C (1993-08-21).

Rain in August

Wet (more than 8 rainy days): about 16 days with 1 mm or more, 104 mm in total. Year to year it varies a lot - the wettest August was 2020 with 177 mm, the driest 1994 with 48 mm. Humidity averages 82%.

Sunshine and daylight

Around 3.7 hours of sunshine a day (estimated from cloud cover), 16.0 hours of daylight: the sun rises about 05:19 and sets about 21:45 local time in mid-August. Average cloud cover is 77%.

Is August a good time to visit Reykjavik?

August is not the strongest month here: cool days and frequent rain. The best months for Reykjavik on our scoring are June, May, July.

Mild by local standards, cool for a summer holiday

August is among Reykjavik's warmer months, but that needs a local frame of reference. Even the warmest 10% of days reach only 16°C or more, so a mild afternoon is a better expectation than proper heat. The coldest 10% of nights fall to around 6°C or below, making a warm layer useful if you plan to stay out late. Pack trousers, tops you can layer and a jacket rather than relying on summer clothes alone. This weather suits travellers who find hot city breaks tiring, but anyone wanting to sit outside in light clothing through the evening is likely to find it chilly.

Long daylight, but keep plans flexible for rain

The useful advantage is daylight: August has about 16 hours a day, giving you room to move outdoor plans around rather than feeling tied to a short sightseeing window. The catch is that sunshine averages only 3.7 hours daily, so long days do not mean consistently sunny skies. Rain is frequent enough that you should be comfortable going out in wet weather, with a waterproof jacket and footwear that can cope. Keep some indoor time flexible and take advantage of brighter spells when they arrive. You need not write off outdoor plans, but a holiday that depends on dry afternoons would be a poor match.