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
Icy spells in the Southern Hemisphere. Snow in the Andes. . . Tuesday 28 July 2026
A composite image showing a temperature radar map of South America and a snow-covered town in Chile. The winter cold is bringing heavy snowfall to the Andes and, in some areas, snow down to lower altitudes.
Tuesday 28 July 2026

Snow in the Andes

Icy spells in the Southern Hemisphere
Europe’s seas are unusually warm. Up to 30 degrees. . . Friday 31 July 2026
Friday 31 July 2026

Up to 30 degrees

Europe’s seas are unusually warm
Heavier rainfall over the week for some. Ireland & Scotland. . . Tuesday 28 July 2026
Split image showing a Europe rainfall accumulation forecast map on the left with the highest totals across the UK, Ireland, and Scandinavia, and a satellite weather map on the right with a broad band of rain stretching across Ireland, Scotland, and northern Britain, highlighted by a rain cloud icon.
Tuesday 28 July 2026

Ireland & Scotland

Heavier rainfall over the week for some
All weather news
This might also interest you
A frozen start to the weekend. Icy conditions. . . Friday 13 February 2026
UK temperature map dated 14.02 showing widespread subzero values in blue shading, with readings such as −4 in Glasgow, −3 in Dublin, and −2 in London, alongside a blue thermometer icon.
Friday 13 February 2026

Icy conditions

A frozen start to the weekend
Bright and warm conditions take hold. Spring-like outlook. . . Thursday 23 April 2026
Split UK map showing warm temperatures up to 21 degrees in orange on the left and clear sunny conditions with temperatures from 12 to 18 degrees on the right, with sun icons across the country.
Thursday 23 April 2026

Spring-like outlook

Bright and warm conditions take hold
Super Typhoon Bavi threatens Taiwan. Up to 1,000 mm of rain. . Weather Videos. Wednesday 8 July 2026
The image shows an intense tropical cyclone over the western Pacific, east of Taiwan and the Philippines. The centre of the system is depicted as a light purple and white vortex with a clearly visible eye, surrounded by a ring of red and orange areas indicating the strongest wind speeds. A white arrow marks the typhoon’s predicted track towards the north-west, in the direction of Taiwan. To the west of the storm lie the Philippines, with the cities of Manila and Cebu; to the north of these lies Taiwan, with Taipei. Further west, the Chinese coast, including Hong Kong, and parts of Vietnam can be seen. The coloured wind map shows predominantly green areas outside the storm’s core, indicating significantly weaker winds. White streamlines illustrate the typhoon’s anti-clockwise circulation in the Northern Hemisphere. The highest wind speeds are concentrated around the eye of the cyclone.
Weather VideosWednesday 8 July 2026

Up to 1,000 mm of rain

Super Typhoon Bavi threatens Taiwan
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