‘Heat dome’ will bake Mediterranean in near-46°C heatwave

Malta will bake in one of the most intense heatwaves of the summer because of a massive heat dome expected to lock in the weather pattern across the southern parts of Europe, centred over the Mediterranean.

Weather analysts Severe Weather Europe forecast an excessive, scorching heat, with the highest temperatures expected across Italy, Malta and Greece through mid-week then intensifying over Spain and Portugal for the weekend.

A textbook weather pattern resulted in extremely high temperatures across parts of the Mediterranean and the Balkans, the worst was in Greece which ended at around 47°C on Tuesday, apart from raging wildfires.

This time, extremely high temperatures will develop across the Mediterranean, first over Italy, Malta, and once again also into the western and southwestern Balkan peninsula, then gradually expanding towards the Alps, as well as Spain, Portugal towards the next weekend.

The ‘heat dome’ has been the dominant feature of summer 2021 in both Europe and the United States. A heat dome is a term used when a large area of high pressure is parked over a large portion of the continent and stays there for days, or even weeks.

The heat dome works like a lid on a pot: the large dome traps a very warm air mass, especially at the lowest elevations, creating a very dry air mass from the African desert, with minimal chances for precipitation, or even clouds.

The result is extreme heat and a significantly enhanced wildfire threat as drought intensifies.

“It will be extremely hot in places, potentially very near or even above 45°C locally. Thanks to very warm temperatures through the lowest levels of the atmosphere, lack of any strong winds, and very dry air mass advection from northern Africa,” Severe Weather Europe analysts said.

Heat domes are becoming a more regular weather phenomenon as entire regions deal with increasingly extreme heat and wildfires. In June, record temperatures hit North America, with more than 100 people dying in the northwestern US and Canada.

In the case of Europe, the jet stream has dipped south across western Europe and extended into northeast Europe, allowing a ridge to develop across southeast Europe. Within the ridge, the air has become warmer day-on-day.

Warm air from a Saharan dust cloud has also contributed to the warmer than usual temperatures. The high pressure from the jet stream ridge and the Saharan warm air has been stuck over southeast Europe for a while, maintaining temperatures 10C to 15C above average.

They are quite common in temperate zones but they are getting more intense and regular in areas that do not usually see such extreme heat. Scientists from the US National Oceanic and Atmospheric Administration (NOAA) found the main trigger is a strong change in ocean temperatures during the preceding winter.

This cascade of deadly extreme weather this summer in the northern hemisphere could make 2021 the year when climate predictions became a reality that can no longer be ignored.

Met office forecasts

The Meteorological Office at Malta International Airport is forecasting that on certain days the temperature will feel as high as 41 degrees.

The seven-day forecast shows that Monday’s highest temperature will hit 35 degrees but it will feel like 37 degrees as the island is swept by a south-southwest wind.

From Tuesday, the mercury will rise to a high of 38 degrees but it will feel like 40 degrees with the wind blowing from the west-northwest. The lowest temperature will be 29 degrees, which will ensure a hot night.

Wednesday will see the temperature continue to rise to 40 degrees and feel like 41 degrees. The wind will blow from the west-northwest at Force 3 and 4. The lowest temperature will be 28 degrees.

On Thursday, the maximum temperature will hit 39 degrees but will still feel like 41 degrees. But the northwest wind will bring with it a cooler night with the forecast predicting a low temperature of 26 degrees.

Wind blowing from the east-northeast on Friday will bring with it a slight reprieve with the highest temperature hitting 33 degrees, although it will feel like 36 degrees. The lowest temperature on the day will be 26 degrees.

And on the weekend, both days will register highs of 36 degrees and feel like 38 degrees with winds varying between northwest and west.

Throughout the week, the UV Index is expected to be a very high 10, which means that protective measures must be taken when exposed to the sun.