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
Split image showing a calm coastal inlet and mountain landscape on the left, and a dramatic layered lenticular cloud above hills and trees on the right.
Sunday 10 May 2026

Your weather - Your shots

Scenic spring views across the countries
Satellite weather map of the UK and western Europe showing rain bands across Britain, a rain cloud icon over Scotland, and a thunderstorm icon near Belgium and northern France on Wednesday 13.05.
Wednesday 13 May 2026

Hail also possible

Thunderstorm risk for parts of the UK
On the left, a map of Europe shows temperature anomalies in April, with positive values in Western Europe and negative values in Eastern Europe. On the right, an industrial area can be seen, with chimneys and trees in the foreground.
Friday 8 May 2026

Record in Spain

Third warmest April on record
All weather news
This might also interest you
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
Split image showing a person in a yellow jacket struggling against strong winds and heavy rain on a street at night on the left, and an Irish wind forecast map on the right with red and purple shading, gusts up to 75 mph, and a wind warning icon, divided by a curved white line.
Saturday 24 January 2026

On this day...

Historic Storm Éowyn arrives
plit image showing a double rainbow over a rocky shoreline on the left and sheep grazing in a green field under stormy clouds on the right.
Sunday 2 November 2025

Your weather - Your shots

Mixed conditions on an unsettled week
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