UK Heat Wave to Make It Harder to Sleep as Health Alerts Raised

(Bloomberg) -- UK authorities upgraded health alerts for England as heat wave conditions are forecast to see London reach 34C (93F) by Saturday.

The British capital will reach 32C on Thursday as a stream of hot air drives up temperatures across the country this week. The UK Health Security Agency raised the alert level to amber for all English regions until 9 a.m. on Monday, warning of significant risks to children, older people and those with health conditions.

The heat from a high-pressure system — drawing in air that will rapidly warm as it descends from over Greenland — won’t dissipate quickly when the sun sets, according to the UK Met Office. That could mean so-called tropical nights with evening temperatures staying above 20C in some parts of the UK, a threshold beyond which many people report trouble sleeping.

“We have some pretty high overnight temperatures,” the Met Office’s Alex Burkill said in a forecast briefing. “It is going to be oppressive.”

Warm evenings can be especially dangerous as they make it hard for people to cool off and recover from daytime heat, especially in the UK and other regions with very little household air conditioning. 

The heat wave is expected to drive up demand for medical and care services, and could also trigger travel delays and transportation disruptions, the UK health agency said.

The high-pressure system driving the UK heat wave is also forecast to raise temperatures across the region, with a number of Spanish regions reaching 40C over the next few days. Paris could touch highs of 37C on Saturday.

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