Netweather TV has shared an update on the possibility of a heatwave, stating that the criteria could be met. The UK heatwave is set to be 'unusual' with temperatures expected to skyrocket to 31C at times this weekend.
Unusually Strong Ridge of Pressure
Nick Finnis from Netweather wrote in a blog post that the UK faces an 'unusually strong' ridge of pressure, which is likely to trigger stifling conditions. He noted: 'Still a few days off this being resolved. But whether the trough pushes through or not, all models indicate a rapid rise in pressure and heights from Sunday, with an unusually strong upper level blocking high developing over or near the UK.'
Finnis added: 'So strong are the forecasts that Percentile ranks of 500 hPa heights are close to record values for May. This strong blocking high driven by large scale subsidence of air deep through the atmosphere from near the top of the troposphere. This subsidence of air causes warming of the air at the surface, so we could see temperatures build rapidly again on Sunday and Bank Holiday Monday in dry and sunny conditions, perhaps into the high 20s Celsius.'
Met Office Forecast
Craig Snell, a forecaster at the Met Office, said: 'Temperatures at the start of the week are still a little subdued for the time of the year; as we head towards the weekend, we are expecting to see a change.' The UK is set to enjoy temperatures in the low-to-mid-20s in the run-up to the bank holiday on Monday.
Met Office meteorologist Annie Shuttleworth added: 'From Thursday onwards, temperatures could rise above average, approaching 20C for some across southern areas. We could be closer to the mid-20s, possibly, for some areas, in the South East, by the bank holiday weekend.'
Heatwave Criteria and Dates
Mr Finnis noted that criteria could be breached over the weekend if Friday, May 22, Saturday, May 23, and Sunday, May 24, are as hot as advertised. The Met Office defines a heatwave as three consecutive days of warmer than usual temperatures, but each threshold differs depending on location.
Earmarking May 22 as the possible start date, Mr Finnis wrote: 'Heatwave criteria could well be met if Saturday as well as Friday turns out hot in the end, with Sunday and Monday looking potentially hot across SE England.' The heatwave could end from Tuesday, May 26, forecasters add.
