UK weather warning system explained: Strong winds forecast for London with Met Office giving yellow alert

The Met Office has issued a yellow wind warning for London, with gusts of more than 40mph set to hit the capital after a sunny weekend. 

The weather agency has the alert in place for most of England and Northern Ireland until 10pm on Monday, which is also set to be the wettest day of the week.

Forecasts have moved into uncharted territory already in 2024, with Storm Kathleen becoming the record 11th ‘named storm’ within a one-year cycle.

The blustery conditions on Monday follow the mercury hitting 21°C on Friday, which made it the hottest day of the year so far.

Monday is the only day the Met Office has a colour-coded warning in place for this week – but what do these alerts mean?

What are weather warnings?

Weather warnings tell people what weather is in store and whether forecasters and other experts deem it to be extreme.

The Met Office operates 24 hours a day, 365 days a year, so warnings can be issued at any time, day or night. These can be for any extreme conditions, be they rain, thunderstorms, wind, snow, lightning, ice, extreme heat and fog.

What are the colours of the UK's weather warnings?

The Met Office issues weather warnings through the National Severe Weather Warning Service. These are for when severe weather has the potential to impact the UK.

Their warnings are given a colour based on the severity of the information. Red is the most serious, followed by amber, then yellow.

What do the colours of the UK weather warnings mean?

The Met Office says on its website:

Yellow warning

"Yellow warnings can be issued for a range of weather situations. Many are issued when it is likely that the weather will cause some low-level impacts, including some disruption to travel in a few places.

"Many people may be able to continue with their daily routine, but there will be some that will be directly impacted and so it is important to assess if you could be affected.

“Other yellow warnings are issued when the weather could bring much more severe impacts to the majority of people but the certainty of those impacts occurring is much lower. It is important to read the content of yellow warnings to determine which weather situation is being covered by the yellow warning."

Amber warning

"There is an increased likelihood of impacts from severe weather, which could potentially disrupt your plans. This means there is the possibility of travel delays, road and rail closures, power cuts, and the potential risk to life and property.

“You should think about changing your plans and taking action to protect yourself and your property. You may want to consider the impact of the weather on your family and your community, and whether there is anything you need to do ahead of the severe weather to minimise the impact."

Red warning

"Dangerous weather is expected and, if you haven’t already done so, you should take action now to keep yourself and others safe from the impact of the severe weather. It is very likely that there will be a risk to life, with substantial disruption to travel, energy supplies and possibly widespread damage to property and infrastructure. You should avoid travelling, where possible, and follow the advice of the emergency services and local authorities."

How does the Met Office issue weather warnings?

Each warning has the same format to make it as easy to understand as possible. The Met Office announces them and sends them to news services.

The warnings detail what weather is forecast, what to expect from this, and what people should do to stay safe.