You may already be suffering from the heat and humidity but as temperatures are forecast to rise and remain at or above 30C this week there will be impacts on some people's health. Others are enjoying it but the heat is going to get more extreme as July continues. Public Health England (PHE) have chosen to take a Met Office service relating to temperature thresholds to enable their staff, patients and services to prepare. The map above only applies to England, other parts of the UK will experience heat and the humidity, although the most extreme conditions are forecast for England, particularly in the SE, East Anglia, the Midlands and eastern England.
Amber — Heatwave action
"Triggered when the Met Office confirms threshold temperatures for one of more regions have been reached for one day and the following night, and the forecast for the next day has a greater than 90% confidence level that the day threshold temperature will be met. This stage requires social and healthcare services to target specific actions at high-risk groups."
The threshold temperatures vary by region but this week SE Britain could see temperatures of 30 to 34C, possibly a few degrees higher. With very light winds, sleeping at night will be uncomfortable. So we move from Alert & Readiness level 2 to Heatwave Action. The service is for health professionals, contingency planners and emergency responders, and is used for planning purposes within NHS England, it is different to the Amber severe weather warnings which are issued for the public about specific weather events such as heavy rain or snow.
Looking at the Regional Risk Values, the Amber areas; West and East Midlands, East Anglia, Southeast England and London, at 90% likelihood "There is a high confidence that threshold temperatures will be reached. Temperatures will be hot and humid through the daytime. Thresholds are increasingly likely to be exceeded through the period, and staying above overnight thresholds."
Just as in extreme, or lengthy cold spells, there can be serious health consequences from too much heat and vulnerable groups are particularly at-risk as the heat continues and .intensifies. Heatwaves can be dangerous, especially for the very young or very old or those with chronic disease. These alerts set off recommendations and procedures to reduce the risks to health as the heat continues for:
People do die from the excess heat, just as there are excess winter deaths, excess summer deaths begin to happen as UK temperatures pass 25C.
Level 3: Heatwave action: PHE will continue to monitor any increases in heat-related illness reported in calls to NHS 111, GP in hours and out of hours consultations and emergency department attendances (on a daily basis, week days only) Then look at how severe the effects are, including the impact on regions and age groups. Any increase in mortality is monitored.
Level 4: Emergency Response: Further monitoring, daily
Advice from the NHS
"Stay out of the sun. Keep your home as cool as possible – shading windows and shutting them during the day may help. Open them when it is cooler at night. Keep drinking fluids. If there's anybody you know, for example, an older person living on their own, who might be at special risk, make sure they know what to do"
There will be impacts on water supplies as people and infrastructure demands increase, on farming and a higher risk of wildfires. Luckily now most schools are closed for the summer holidays but holiday child care providers still have to manage their settings safely. Often air pollution levels rise in the still, hot air, there are signs of issues for SE Britain by Thursday on the DEFRA air quality forecast
What would it take for a Level 4 , Emergency Response?
"Declaring a Level 4 alert indicates a major incident. The government will decide whether to go to Level 4 when there is a very severe heatwave which will last for a considerable period of time and will also affect transport, food and water, energy supplies and businesses as well as health and social care services. The decision to issue a Level 4 alert is made at national level and will be taken in light of a cross-government assessment of the weather conditions, co-ordinated by the Civil Contingencies Secretariat (Cabinet Office). A Level 4 alert is not triggered automatically by a greater than four day period of severe hot weather"
This would happen when major issues with transportation network, power supplies, water supplies, health and the environment start to occur.
Heatwave Plan Wales 2012