As Malta and the rest of Europe brace for a spell of cooler, windier, and more unsettled weather in late July, many may wonder if this is out of season. Surprisingly, it's not.

According to Maltese Islands Weather, this brief break from the heat is a recurring feature in Europe’s summer weather patterns and is backed by decades of historical weather data.

At the heart of this phenomenon lies the jet stream; a fast-moving ribbon of air high in the atmosphere that influences Europe’s weather systems. In early to mid-summer, the jet stream usually stays farther north, allowing high-pressure systems to dominate and triggering the kind of heatwaves we often experience. However, by late July or early August, the jet stream starts to undulate, dipping further south due to a few key factors.

One of the main reasons is the waning solar input after the summer solstice; daylight hours start to decrease, and land-sea temperature contrasts grow more pronounced. While Europe’s landmass heats up quickly, the Atlantic Ocean remains cooler. This contrast helps destabilise the atmosphere when the jet stream becomes more erratic.

This shift can cause omega blocks and heat domes to collapse, leading to spells of cooler, wetter, and windier weather. Statistically, this change is more likely to occur during weeks 30 to 32 (approximately July 25 to August 10).

In Malta, this transitional period marks the end of the hot and dry phase of summer and ushers in the hot and humid conditions. So, while it may feel strange in late July, it’s all part of the natural rhythm of Mediterranean summer.

Are you enjoying this week’s cooler temperatures?