France Likely to Avoid a Heatwave in June – Meteorological Channel News
In a surprising turn of events, France is unlikely to experience a heatwave in the month of June this year. While it may be too early to predict the exact weather patterns for the month, medium-term forecasts do not anticipate the arrival of summer weather and heat across the country. This deviation from the norm has raised eyebrows, shedding light on the underlying meteorological phenomena at play.
Last year, June saw scorching temperatures and frequent thunderstorms. However, this year presents a starkly different scenario, at least for the first half of the month. Following the trend from May, cold fronts are persisting, indicating unstable and relatively cool weather. This pattern is attributed to the behavior of the jet stream, high-altitude winds that meander across the atmosphere. These meanders bring down cold air from the Arctic on one side, while warm air is pushed in the opposite direction, resembling a pendulum swing. What is noteworthy is the blockage of this transition. Instead of alternating between cool spells and heatwaves, some areas are enduring prolonged periods of cool air, while others are experiencing persistent heat. In June 2022, when France faced a heatwave with temperatures reaching up to 43°C, the country was on the warm side of the jet stream. This year, however, France finds itself on the cooler side of the stream due to the « Omega blockage » phenomenon.
The jet stream’s pattern resembles the Greek letter « Omega, » hence the term « Omega blockage. » Last year, Western Europe, including France, experienced record-breaking early heatwaves due to the warm side of this blockage. Conversely, this year sees France on the cooler side, influenced by the jet stream extending from the North Atlantic to the Iberian Peninsula and Morocco. Unusual cold temperatures have been observed in Iceland, while snowfall has graced the Scottish Highlands in recent days. Meanwhile, the warm air is surging towards Eastern Mediterranean countries like Greece and Turkey, where temperatures are expected to soar.
At a European scale, the jet stream’s meanders and the interplay of air masses mirror the conditions of June 2022, albeit in reverse. This « mirror effect » has drastically different impacts on the countries involved, with some experiencing cool spells instead of heatwaves, and vice versa. Over the past decade, there has been a significant duration of these blockage situations, which once established, persist for weeks or even entire months. This year’s recurrence of cold fronts over France since the beginning of spring suggests a prolonged period of unsettled weather. Long-term meteorological models do not foresee an end to this pattern, with cold air continuing to descend from the Atlantic side, while hot air rises towards Eastern Europe, and even reaching Finland. With the cooling trend settling over France, June is likely to be cooler than average, potentially breaking the streak of 28 consecutive months above normal temperatures. However, a sudden shift in weather patterns towards the end of the month could swiftly reverse this forecast.