What's in the photo? A spiraling cloud front hugging the coastline.This striking photo shows an unusual cloud spiral nestled perfectly along the west coast of the Iberian Peninsula in 2017.
However, in this case, the rotation was much slower and weaker than the rotation during tropical storms, so the cloudy and dry air did not fully mix together, which prevented a proper vortex from forming. This also stopped any clouds from passing over the land. An extreme heat wave that swept across Southern Europe in July 2017 also created an usually large temperature difference between the cloudy, sea air and the dry, land air. This may have further prevented the two fronts from mixing, helping to create the stunning spiral shape. When this photo was taken, temperatures in Spain and Portugal were above 104 degrees Fahrenheit , according to NASA's Earth Observatory.
By submitting your information you agree to the Terms & Conditions and Privacy Policy and are aged 16 or over.Interestingly, marine stratocumulus clouds normally only appear along the western coasts of Earth's landmasses, according to NOAA. This is because they form when cold water from the deep sea is brought to the surface by Earth's spin — also known as the Coriolis effect — which cools the air above and enables water vapor to condense into clouds.