Did you notice the frost looking a little unusual, with a ‘spiky’ appearance this morning? That's because it wasn't your typical frost.
The frost was created by fog, called ‘freezing fog.’ Freezing fog develops when the water droplets within the fog touch something that is below 32 degrees.
The droplets immediately freeze on contact, with each droplet freezing upon the last. This creates a jagged or dagger appearance.
While pretty to look at, this can be dangerous in winter as it could lead to slippery roads.