A marine heatwave is causing concern as experts warn that great white sharks may start appearing more frequently along British coastlines. The Met Office predicts that prolonged periods of warm sea temperatures could lead to an influx of Mediterranean species migrating to UK waters. Oceanographer Jim Dale cautioned that this shift could result in the decline of native marine species such as cod, while introducing new threats like sharks, jellyfish, toxic algal blooms, and pollution to British beaches.

The ongoing heatwave is expanding northwards in the UK, with temperatures expected to reach 34C in some areas. The UK Health Security Agency issued an amber heat health alert for the Northest of England, effective until Sunday night. The rise in sea surface temperatures, up to 5C above average in parts of Wales and England, is indicative of a potential extreme marine heatwave, a rare occurrence in the UK.

Mr. Dale highlighted the ecological impact of the warming seas, noting the potential for harmful algal blooms and increased risks for beachgoers. He expressed concerns about the changing marine ecosystem, mentioning the likelihood of great white sharks being drawn to British waters due to the availability of new prey. This phenomenon, driven by the warming oceans, could also attract other species like hammerhead sharks and box jellyfish to UK shores.

The Met Office attributed the current marine heatwave to a heat dome, marking the third and most severe heatwave of the year. This event is expected to have far-reaching consequences on marine life, potentially leading to mass mortality events for certain species. As high pressure persists, temperatures are set to rise further in Scotland and northern England, reaching the mid-20sC in Northern Ireland and Scotland, and up to 34C in the Midlands and Southeast of England.

Looking ahead, a cooling trend is forecast for the south and Midlands on Saturday, followed by the risk of thunderstorms. Deputy Chief Forecaster Tom Crabtree indicated that while temperatures may decrease in some areas, warm weather will persist, especially in the southwest. The focus of the heatwave is expected to shift, with the potential for continued warmth in many parts of the UK alongside the possibility of thunderstorms in the south and southwest.