Weather outlook for the solar eclipse on Wednesday, 12 August

Today, a low-pressure system is situated just south of Reykjanes, with its associated front moving across most of Iceland. The low is then expected to move eastwards along the south coast. Precipitation will mainly be confined to southern Iceland, while Breiðafjörður and the Westfjords should see less precipitation until the evening, when the front appears likely to move across the area. The best chance of breaks developing in the cloud cover around the time of the solar eclipse is therefore likely to be in this region. Northern Iceland will remain dry until later in the day. More detailed forecasts for each forecast area in western Iceland, with particular reference to the solar eclipse, can be found below.

The Icelandic Met Office models distinguish between three cloud layers: high, mid-level and low cloud. High clouds have little effect on visibility during a solar eclipse, as sunlight can pass through them relatively easily. They can, for example, produce a halo around the sun. Mid-level clouds allow less sunlight through, but it may still be possible to enjoy the eclipse. If an area of low cloud is present, however, there is little chance of seeing the sun. The eclipse will nevertheless still be noticeable under such conditions.

The total cloud cover forecast indicates that skies will be almost completely overcast across Iceland at 18:00 (green image), although breaks in the low cloud are most likely around Breiðafjörður and in the Westfjords. In southwest Iceland, unstable atmospheric conditions and showers are expected. This means that the sun may appear between showers and, with luck, one of these breaks could coincide with the solar eclipse.

The upper image is from the latest run of the IG high-resolution model, while the lower image shows the DINI high-resolution model.

Cloud cover forecasts are among the most difficult forecast products to model, as the underlying physics is highly complex. Small breaks shown in the cloud cover should therefore be treated with caution. The forecasts indicate that breaks could develop somewhere within the area, but their precise location cannot be predicted.

The nationwide forecast for Wednesday is as follows:

Easterly winds of 5 to 13 m/s, strongest along the south coast. Rain or showers, but less precipitation in northern Iceland until later in the day. Temperatures between 10 and 20°C, warmest in the north.

The precipitation forecast maps below, from the Icelandic Met Office’s IG and DINI high-resolution models and valid at 18:00 on Wednesday, show where rain is expected and the extent of the affected area. Once again, they demonstrate the difficulty of predicting the exact location of the precipitation.

Weather outlook along the path of totality

Capital region

Light easterly or northeasterly winds, cloudy with showers. Breaks may develop between showers, allowing the solar eclipse to be seen, although the chances are not high.

Reykjanes Peninsula

Conditions will be similar to those in the capital region, with northeasterly winds and showers. There is only a slight chance of breaks developing in the cloud cover.

Snæfellsnes

Easterly winds and probably cloudy with showers. As the front is likely to dissipate around the time of maximum eclipse, there is a chance that the low and mid-level cloud cover will break up in places.

Westfjords

Light northeasterly winds with isolated showers. High cloud is expected, with broken low cloud in western parts and possible breaks in the mid-level cloud, particularly in the northwest. There is some chance of seeing the eclipse in this area.