Dr Ranj Singh said people often get wrong when the worst time to go out is in the heat (Image: BBC)
Scorching heat is set to hit the UK with temperatures rocketing on Wednesday. Up to 40C could be seen in some parts of the UK with a red alert health warning issued by the Met Office and UK Health Security Agency. Now an expert has explained the “3pm rule” which people should abide by to avoid the worst of it and potentially higher risk of heath problems. Dr Ranj Singh, a doctor and TV presenter, has revealed a crucial tip for the heatwave.
Retailers are reporting soaring sales of fans, ice cream makers and sun cream as households try to cope with the extreme heat.Currys said it had seen an almost 1,500% increase in customers searching for fans on its website compared with last weekend, and a 3,500% increase in searches for air conditioning products over the same period.
With a heatwave happening right now, Dr Ranj shares how the heat can impact everyone and offers simple advice to stay safe.
Watch ?????? //bbc.in/morninglive pic.twitter.com/z1ngGnDm8J
— BBC Morning Live (@BBCMorningLive) June 23, 2026
Dr Ranj Singh said: “I just want people to be sensible. So, firstly, think about timings. Everyone wants to go out in the middle of the day. We know the sun’s at its highest between about 11am to 3pm, but the heat is actually at its highest slightly later.
“It’s sort of 3pm to 5pm. Why is that? Because buildings and the roads absorb the heat during the day and they radiate it back out again. So try and delay your any social activities to a little bit later in the evening ideally when it’s a bit cooler.”
In terms of helping those who are vulnerable Dr Ranj said: “This is really important. So, we’re talking about people who might be very young, might be very old, might be pregnant, might have underlying medical conditions.
“Really important to check in on them, make sure they’ve got adequate supplies. I always make a point about breastfeeding babies. Make sure they’re feeding properly.”
Temperatures are set to soar this week (Image: Getty)
He adds: “They might want to breastfeed more often. Things I want people to look out for firstly heat exhaustion is what happens when you’re exposed to heat for a long period of time and your body is still able to cope and still able to do stuff.
“Okay, so for that you want to cool down. You might want to move to cooler earlier, take your clothing off, have drinks, fans, etc.
“If you are not able to cool down adequately, then you’re veering into heat stroke territory and that is a medical emergency. We want you to cool them down rapidly.
“You might use cool packs in the neck and in the groin in the armpits and you want to be calling 999. The sign of heat stroke and heat exhaustion.
“There’s some great stuff on the NHS website if people want to know what signs they need to look out for.”
Symptoms of heat exhaustion and heatstroke:
Symptoms of heat exhaustion
The symptoms of heat exhaustion include:
- tiredness
- dizziness
- headache
- feeling sick (nausea) or being sick (vomiting)
- excessive sweating and skin becoming pale and clammy (a change in skin colour can be harder to see on brown or black skin)
- cramps in the arms, legs and stomach
- a high temperature
- being very thirsty
- feeling irritable
The symptoms of heat exhaustion are often the same in adults and children, reports The Mirror.
If someone is showing signs of heat exhaustion they need to be cooled down and given fluids.
Symptoms of heatstroke
The symptoms of heatstroke include:
- a very high temperature
- hot skin without sweating
- fast breathing and a fast heartbeat
- confusion and restlessness
- seizure (fit)
- loss of consciousness
Heatstroke is a medical emergency. Get immediate medical help if someone has the symptoms of heatstroke – you can check advice on the NHS website.