Blue Lagoon Temperature by Month

The average annual maximum temperature in Blue Lagoon, Reykjanes, Iceland is 9°C (48°F), with daytime highs ranging from 5°C (41°F) in February to 14°C (57°F) in July. This page covers monthly averages, day-night differences, and how Blue Lagoon compares to cities worldwide.

Seasonal changes in Blue Lagoon bring a little variety without extreme temperature swings. Nighttime lows range from 10°C (50°F) in July to 0°C (32°F) in February.

The chart below illustrates the average maximum day and minimum night temperatures in Blue Lagoon by month:

Daily lows are most common between 4 AM and 6 AM. By 3 PM temperatures reach their daily high, driven by peak solar heating. July, the warmest month of the year, receives 168 hours of sunshine.

The chart below shows the average temperature throughout the year:

Blue Lagoon's average annual maximum temperature is 9°C (48°F). To put that in context, here's how it compares to a few well-known destinations:

Barcelona, Spain has an annual average of around 21°C (70°F), with warm summers and mild, fairly short winters.

On the cooler end, Oslo, Norway averages just 10°C (50°F) annually, with pleasant summers but long, cold winters.

Shanghai, China averages 21°C (70°F) a year, with warm summers, mild winters, and a noticeable spring and autumn.

Perth, Australia averages 25°C (77°F) annually, with a classic Mediterranean climate, hot dry summers and mild wet winters.

Temperature alone doesn't tell the whole story, humidity plays a big role in how warm or cold it actually feels. High humidity in summer makes the heat feel more intense, particularly once temperatures climb above 25°C. In winter, the same humidity can make cold air feel sharper than the thermometer suggests.

In the cooler months, when temperatures drop below 10°C, high humidity makes the cold feel more cutting than it would in dry conditions.

In Blue Lagoon, February is the coolest month, with average highs of 5°C (41°F) and humidity around 79%, considered high. For a full picture, see our humidity page.

Climate temperature data is typically calculated as a 30-year average. This smooths out year-to-year variability and gives a more reliable picture of what a place is actually like, rather than what happened in any single unusual year.

The readings come from a range of sources, land-based weather stations, ocean buoys, ships, and satellites. That data is collected by weather services around the world, then pooled, quality-checked, and averaged to produce the climate records you see here.

Seasonal temperature shifts influence more than just how warm it feels, they also drive changes in rainfall, cloud cover, and wind patterns throughout the year.

Warmer air holds more moisture, which tends to mean heavier or more frequent rain during the warmer months. When temperatures drop in winter, any precipitation that does fall is more likely to come as snow or sleet, though in Blue Lagoon this rarely lasts long on the ground.

For more on Blue Lagoon's weather, including monthly rainfall, sunshine hours, and humidity, visit our Blue Lagoon climate page.