What do the different heatwave levels mean? Mini heatwave blasts UK in October
As the UK has its warmest October in five years, much of the country can expect to enjoy mild weather this week.
On Sunday, the temperature in London’s Kew Gardens reached a high of 25.8°C, compared to the 16°C norm for the area at this time of year. While in Cardiff’s Bute Park, the temperature reached 24.4°C.
The Met Office says the weather is set to continue with the Southenjoing the best of the unseasonably warm weather. The hottest areas in the country will be London and the South-East.
It said: “A mostly calm start to the week, but some fronts will linger across Northern Ireland, Southern Scotland, and Northern England.
“These will bring thicker clouds and drizzle. Mostly dry elsewhere, with sunny spells breaking through mist and cloud lingering along some coasts. Unseasonably warm for October, with temperatures 5°C - 8°C above the average.”
Parts of Scotland will still, unfortunately, face heavy rain.
“Rain, heavy at times, for Western Scotland. Cloud lingering around some western and southern coasts. Fine for many others with warm, if hazy, sunshine. The fronts will continue moving southwards, reaching Wales and Central England on Wednesday. Heavy rain across central areas. Warm to the south, though rather cloudy. Turning cooler to the north, with sunshine and showers.”
In the latest Met Office 10-Day Trend video, presenter and meteorologist Alex Burkill said: “The jet steam is going to push its way northwards ahead of the weekend, which will allow for some very warm air to come in from the south.”
But is it a mini heatwave, and how do the Met Office rate an official heatwave level?
What do the Met Office’s heatwave levels mean?
The Met Office will sometimes issue weather warnings if temperatures exceed certain levels. These are predominantly to help healthcare services and workers.
“Should thresholds for an alert be reached outside of this period, an extraordinary heat-health alert will be issued and stakeholders are advised to take the usual public health actions,” the Met Office website states.
There are five levels in place, here’s what they are and what they mean:
Level 0
The first level entails long-term planning to avoid the risks and complications involved with heatwaves, along with “year-round joint working to reduce the impact of climate change” and discovering ways to adapt to the temperatures.
It mainly exists to remind authorities of the importance of and need for planning ahead for the warmer periods.
Level 1 – Green – Summer preparedness and long-term planning
The Met Office uses level 1 throughout summer to stay vigilant as temperatures rise. Social and healthcare services will be working to ensure that they are prepared for extreme weather.
Level 2 – Yellow – Alert and readiness
The level 2 alert is rolled out when the risk is “60% or above for threshold temperatures being reached in one or more regions on at least two consecutive days and the intervening night”.
This is when social and healthcare services will be on high alert and working to try to ensure the heatwave does not cause harm to people and patients.
Level 3 – Amber – Heatwave action
The Met Office has triggered a level 3 heatwave warning to parts of the UK. This is when the threshold temperature has been reached for one full day and the following night, while the following day also has a 90% chance of hitting the threshold temperature again.
Healthcare and social services and workers will now be taking action to protect high-risk groups who may not fare well in soaring temperatures.
According to the NHS website, those most at risk include:
Older people – especially those over 75
Those who live on their own or in a care home
People who have a serious or long-term illness – including heart or lung conditions, diabetes, kidney disease, Parkinson's disease or some mental health conditions
Those who may find it hard to keep cool – babies and the very young, the bedbound, those with drug or alcohol addictions or with Alzheimer's disease
People who spend a lot of time outside or in hot places – those who live in a top-floor flat, the homeless or those whose jobs are outside
Level 4 – Red – National Emergency
The fourth and final warning level means a heatwave has continued for so long at such high temperatures that its effects “extend outside the health and social care system”.
The Met Office warns that death and illness may occur among the fit and healthy at this stage, as well as in high-risk groups.