During May and June, the cold water of the Pacific Ocean creeps inland, producing low clouds and fog along California's coast and inland valleys.

Called the marine layer, it can produce grey and chilly days along the immediate coast well into June, and as seen in the video above, even appears on our WeatherRadar.

This layer appears when a warm, dry air mass passes over the cooler waters of the body of water. The air close to the water cools and becomes saturated, leading to low-level clouds.

If you spot fog over a body of water near you, be sure to check the WeatherRadar to see it replicated in the app.