Merchants’ Weekend (Verslunarmannahelgi), starting today, is the biggest weekend for travel in Iceland. Almost everyone is going somewhere. Reykjavík is empty of Icelanders, but full of tourists.
We have numerous sources for weather forecast. The official vedur.is is more pessimistic than some of the others. Of course the weather in Iceland is about as stable as the eonomy and politicians, but if you are not happy with our forecast go to: belgingur.is, yr.no or the Weather Channel. At least one of those should insure good weather, wherever you are.
The best weather to tomorrow, according to vedur.is, will be in Öræfasveit, SE Iceland, and in the southern part of the West-Fjords, sunny and 14°C / 57°F. The worst weather will be in Vopnafjörður, NE Iceland, rain and 7°C / 44°F.
The best weather on Sunday will be in Vopnafjörður and in Vestmannaeyjar island, were the biggest music festival in Iceland is held, every year since God knows when. Temperature 13°C / 55°F. The worst weather will be in Reykjavík, the same temperature but rain. The other sources all say Reykjavík will be fine. So if you are not happy with the outcome sue the ones that had it wrong (but not us).
On Monday, a public holiday, the best weather will be at Snæfellsnes peninsula West Iceland, 12°C / 53°F and partly sunny. The worst weather will be in Öræfasveit, the location of Skaftafell, and Jökulsárlón glacier-lagoon, 9°C / 48°F and heavy rain.
Just remember that the Icelandic summer weather is like sex. Even if it is bad, you usually survive.