Originally Posted by Out of my Element

These are the two key websites. And you need to know how to translate wind speeds that are reported in Iceland as "Meters per Second" into "Miles per Hour", as there are regular road signs in Iceland reporting temperatures (in Celsius) and windspeeds (in meters/second). These signs are almost always before mountain passes as temps are usually lower there and winds are usually stronger. There's a good explainer here:

https://www.tripadvisor.com/ShowTopi...s-Iceland.html

This is what a weather sign looks like:




Wind Direction, speed, temperature, and gusts are the 4 categories on the Kjalarnes part of the sign. A quick and dirty meters/second to miles/hour rule of thumb is to double the windspeed and add a bit more to convert, so 18 mps = about 40 mph (the ratio is actually about 2.25/1). So those 25 mps gusts are actually 55 mph winds and that's VERY common in Iceland and will blow a camper right off of the road.