Expected heatwave triggers heat-health alert
As I wrote in my blog last Friday, a spell of hot and humid weather is on the way in the coming days, with temperatures across eastern parts of England expected to reach 30C (86F).
The cause of rising temperatures is a plume of heat and humidity moving up from Spain, bringing what are expected to be the highest temperatures experienced in the UK so far this year.
In response to the arrival of the hot weather, the Met Office today issued a level 2 heat-health alert for the Midlands and eastern parts of England.
This warning is triggered when the Met Office forecasts that there is a 60 per cent or higher chance of temperatures being high enough on at least 2 consecutive days and the intervening night to have a significant effect on health.
During hot spells, vulnerable sections of the population, such as the very young and elderly, feel the effects of heat more than others – especially those that suffer from serious illnesses.
However, whilst the issuing of this alert may seem startling, it is July and heat and humidity of this nature are not unusual for this time of year.
Nevertheless, the following advice is being offered as a precaution;
– try to keep out of the sun between 11am to 3pm
– apply sunscreen of at least SPF15 with UVA protection
– wear UV sunglasses, preferably wraparound, to reduce UV exposure to the eyes
– wear light, loose-fitting cotton clothes, a hat and light scarf
– drink lots of cool drinks
– look out for others especially vulnerable groups such as older people, young children and babies and those with serious illnesses
– never leave anyone in a closed, parked vehicle, especially infants, young children or animals
Intense thunderstorms to break the heat
If you’re not a fan of the heat and humidity, you’ll be pleased to hear that temperatures are going to fall back a bit at the weekend.
However, in the process of that happening, some intense thunderstorms are expected to spread northwards across the UK during Friday night and Saturday.
These thunderstorms will deliver frequent lightning, hail and gusty winds, with the potential for some disruption – something for which the Met Office has issued a warning.
What will cause the intense thunderstorms to form?
Weather is driven by contrasts in temperature, pressure and humidity (moisture levels), with the most active weather taking place when these contrasts are most extreme.
When it comes to thunderstorm formation, it is down to the collision of cooler air with warm, moist air. As the two collide, the warm, moist air is thrown way up into the atmosphere to around 30,000ft – the height at which commercial airliners fly.
It is effectively like taking the lid of a saucepan of cooking popcorn, resulting in the bubbles of air rushing rapidly upwards in the atmosphere, forming cumulonimbus clouds that produce thunder, lightning, heavy rain, hail and gusty winds.
At the moment, there is still some uncertainty about the areas that will see the most intense thunderstorms, so keep an eye on the Channel 4 Weather website for the latest forecast. I’ll also be posting updates on Twitter – @liamdutton