Met Office maps turn red over Wales as health alert issued

North Wales Live

5 hours ago

Pollen counts are increasing across large parts of the UK as the heat builds, the Met Office has warned. Hay fever sufferers in Wales are being advised to keep tissues handy over the next three days.
The Met Office said 'very high' pollen counts will be seen over the country from Wednesday to Friday, June 18-20. This red level alert is the highest for pollen that's issued by the forecaster.
Grass pollen is rated the main threat in Wales, with weed pollen levels expected to remain 'moderate'. The former is the trigger for the majority of hay fever sufferers, with counts of between 50 and 150 grains per cubic metre likely this week.
The warning applies to much of southern Britain. Slightly lower pollen levels are forecast for northern England, while parts of Scotland are currently experiencing 'low' amounts of pollen.
Complicating the picture is the current surge in Covid cases and the emergence of a new variant, NB. 1.8.1, also known as Nimbus. This too produces symptoms like sneezing, headaches and, in some cases, loss of smell. The main difference between hay fever and Covid is a high temperature in people with the coronavirus.
Britain is currently braced for a likely heatwave in which parts of the country could experience extreme temperatures. The Met Office estimates the mercury could reach 33C in southeast England and some online forecasters are tipping the mid-30s.
While it won't get as hot in Wales, the Met Office is forecasting 29C in parts of northeast Wales on Friday, June 20. Temperatures will dip slightly further west and the risk of rain hasn't been excluded completely from the forecast. Join the North Wales Live Whatsapp community now
Levels of pollen and how it is dispersed is affected by the weather. If temperatures reach between 18-28C, the Met Office said grass pollen counts will rise, especially if it's dry with low humidity and a gentle breeze.
Sunshine is also associated with high pollen levels as this is crucial for photosynthesis, the process by which plants produce pollen. Ironically, pollen levels fall when temperatures surpass 28C.
It's possible Wales will reach official heatwave thresholds in the coming days. For this to happen, temperatures of 25C must be experienced on three successive days. Across Greater London and the Home Counties the threshold is higher, at 28C.
Tony Wisson, deputy chief meteorologist at the Met Office, said: 'By the beginning of the weekend we could very well be meeting heatwave thresholds in places. Sign up for the North Wales Live newsletter sent twice daily to your inbox
"While the warmest temperatures are likely across London and the east of England, by Saturday heatwave thresholds could be reached across much of the Midlands, low-lying areas bordering the Peak District and even parts of east Wales.'
Five-day heat-health alerts have been issued by the UK Health Security Agency for six regions of England from 12pm on June 18 until 6pm on June 22. Vulnerable groups, including those aged 65 and over or those with pre-existing health conditions, are likely to be affected by rising temperatures, the agency warns.
After Friday's peak in Wales, the Met Office expects another warm day on Saturday, June 21, though a couple of degrees cooler. Sunday's temperatures are expected to fall further in Wales. Eastern England could retain its heat into next week, leading potentially to some very high readings over the weekend.
A breakdown in the conditions is forecast for early next week, though there's still some uncertainty when this might happen. Depending on the position of the jet stream, another ridge of high pressure may push in towards the end of next week, potentially leading to a repeat scenario playing out.