Home
Weather Dublin
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
    Home / Editor's Pick /

    Autumn feature explainer: It's fog season!

12:00
21 November 2023

Autumn feature explainer
It's fog season!

fog

As high pressure draws in and the weather settles down, we're more likely to start seeing some more seasonable features like fog.

Autumn and winter is the perfect time for fog to develop, especially in periods of high pressure dominated weather, with weaker winds allowing dense, stubborn fog to settle, even for days at a time.

This is because in the cooler months, under clear skies at night, heat from the ground can quickly escape allowing for the temperature to drop below the dew point.

There are several types of fog that form in different ways, including valley fog, radiation fog, advection fog. Sea fog, often a result of advection fog, is known as 'haar' or 'fret' in some parts of the UK. It is most common along North Sea coasts.

Because of the many factors involved, forecasting the arrival and exact location of fog is actually quite tricky. If just one aspect of the development is out of sync, fog is unlikely to form.

Cloud cover, wind speeds, temperature, moisture levels, and daylight hours all play a role.

Why is fog hard to forecast?read more

A different type of fog can also occur in sub-zero temperatures, this is called freezing fog and will become a more likely occurrence in the depths of winter, rather than autumn.

The water droplets from the drizzle in the fog become supercooled, still remaining in liquid form in the sub-zero air.

Did you know?

You can even spot fog on the WeatherRadar!

They then freeze instantly upon coming into contact with an object or surface, creating what is called rime. This is a layer of tiny ice crystals, creating wintery landscapes.

To learn more on exactly how and why fog forms, check out our Weather Explained video below:

Weather & Radar editorial team
More on the topic
June heatwave also heated up the oceans. Across Europe's waters. . . Wednesday 1 July 2026
Europe temperature map with sea temperature icons showing coastal water temperatures of 20–24°C around the British Isles, 20–25°C in the Baltic Sea, 25°C in the Black Sea, and 25–27°C across parts of the Mediterranean.
Wednesday 1 July 2026

Across Europe's waters

June heatwave also heated up the oceans
A hot and thundery week. Your weather - Your shots. . . Sunday 28 June 2026
Split image showing a bright branching lightning bolt illuminating pink storm clouds on the left and a vivid rainbow arching above a rocky coastline and calm sea beneath dark clouds on the right.
Sunday 28 June 2026

Your weather - Your shots

A hot and thundery week
Frost instead of a heatwave. Winter in South America. . . Friday 26 June 2026
Temperature map of South America showing a widespread cold air outbreak across Argentina, Uruguay, Paraguay, and southern Brazil, with a large blue thermometer icon highlighting below-average temperatures and near-freezing conditions in parts of Argentina.
Friday 26 June 2026

Winter in South America

Frost instead of a heatwave
All weather news
This might also interest you
Turbulent weather in the Canary Islands. Storm and rain. . . Friday 12 December 2025
Weather graphic showing rain and wind fields over the Canary Islands and a central warning symbol.
Friday 12 December 2025

Storm and rain

Turbulent weather in the Canary Islands
Seasonal warmth between spring thunder. Your weather - Your shots. . . Sunday 19 April 2026
Split image showing coastal sunset with layered lenticular clouds over rooftops and palm trees on the left, and a green valley with river and hills under soft daylight on the right.
Sunday 19 April 2026

Your weather - Your shots

Seasonal warmth between spring thunder
Long-term trends need a pinch of salt. 40 °C in July?. . . Tuesday 30 June 2026
Temperature radar of 2022 heatwave where the all-time temperature record in the UK was set. Warning symbol overlain.
Tuesday 30 June 2026

40 °C in July?

Long-term trends need a pinch of salt
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwitteryouTubelinkList