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
A wet start before conditions settle. Commonwealth Games 2026. . . Wednesday 22 July 2026
Split image showing a weather map for western Scotland with widespread rain around Glasgow on the left, and runners poised at a starting line on an athletics track on the right.
Wednesday 22 July 2026

Commonwealth Games 2026

A wet start before conditions settle
New heatwave in southern Europe. Up to 45 degrees in Spain. . . Tuesday 21 July 2026
Split temperature map showing extreme heat across Spain on the left and Greece on the right, with temperatures reaching 44°C near Murcia, around 40°C in parts of Greece, and a large thermometer icon highlighting dangerous heat.
Tuesday 21 July 2026

Up to 45 degrees in Spain

New heatwave in southern Europe
Rain returns to end dry spell in places. Jet stream delivery. . . Thursday 23 July 2026
Split weather graphic showing widespread showers across the UK and Ireland on the left, and a wind forecast map on the right with a windsock icon and gusts of 25 to 35 mph, highlighting breezy conditions across the two countries.
Thursday 23 July 2026

Jet stream delivery

Rain returns to end dry spell in places
All weather news
This might also interest you
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
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
Storm Chandra makes impact. Severe gales & heavy rain. . . Tuesday 27 January 2026
Split image showing strong winds over the UK on a forecast map and widespread rain and snow on a weather radar map.
Tuesday 27 January 2026

Severe gales & heavy rain

Storm Chandra makes impact
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