Melburnians have woken to their third morning in a row with widespread thick fog, immersing the city and suburbs in a blanket of cloud on the ground.

It’s being caused by a very stable weather pattern with high pressure sitting over the southeastern parts of the country — taking cool, dewy nights and light winds and producing a thick fog.

The first fog on Monday didn’t last long, but Tuesday’s lasted until well into the afternoon in some western parts of Melbourne and Geelong, as well as the Bellarine Peninsula.

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Then the next fog was already kicking off at Avalon Airport just a few hours after sunset last night.

Laverton. Credit: Daniel Listro

The positioning of the high means that Melbourne is in the perfect spot to see this outbreak of fog — and the western suburbs are primed to keep it hanging around the longest.

With the centre of the high just to our east, the light morning winds are very gently blowing from the northeast. That helps clear the fog over the eastern suburbs first, and consolidates it on the western side of the bay.

A street in Point Cook. Credit: Shawn Stutsel

But there is a special feature that we have over Port Phillip Bay, known as the Spillane Eddy.

Researched by Dr Kevin Spillane at CSIRO back in the 1970s, it is when a morning fog clears the eastern suburbs, but doesn’t quite clear over the Bay. It sits there, just out over the water, lingering in the afternoon.

Our winds don’t remain northeasterly all day, instead turning light south to southwesterly as the afternoon seabreeze kicks in.

So, all that foggy cloud can start to drift back over land once again — like we saw yesterday afternoon in Albert Park, just southeast of the city.

Wyndham Vale. Credit: Diti Mehta

There is one more fog likely in this series of foggy days — on Thursday.

By the end of the week the high moves too far to our east, and the next weather system approaches, so our winds are no longer light or gentle, becoming a bit breezy by Friday morning.

That means we’ll be much less likely to see a fog on Friday, or at least it won’t last very long.

Looking at the city from Coburg on Wednesday morning. Credit: Parham Shabazi

The fogs eventually clear to sunshine — the above photo showing just some wispy high cloud while the eerie fog only just brushes the city on Wednesday.

And the dry conditions are likely to persist well into the weekend, with rain only slowly developing as we go into Sunday.