June hotter than average as first heatwave of the summer recorded

June proved to be warmer and sunnier than average in 2025, with the first summer heatwave recorded in Malta just as the month drew to a close.

The month was markedly hotter than usual, with air temperature lingering at an average of 26.3°C, which is 2.3°C above the climatic norm, throughout the month.

The hottest day was recorded on the 9 June, with a temperature of 35.6°C, while the coolest day of the month was the 1 June, when a temperature of 15.8°C was recorded.

The start of the astronomical summer also brought with it the first heatwave of the season, lasting for four days between the 24 and 27 of June.

A hot period is considered to have reached heatwave status when the average maximum temperature is at least 5°C higher than the monthly norm (in this case 28.8°C) for three or more days. Temperatures reached 34.2°C on the 24 June, 35.3°C on the 25 June, 35°C on the 26 June and 35.2°C on the 27 June, respectively.

The seas also didn’t see much reprieve from soaring temperatures, with the mean sea surface temperature reaching 25.1°C in June, which is higher than the climatic norm of 22°C.

The start of summer also brought with it a dramatic increase in sunshine, with June seeing an increase of 40.2 hours of bright sunshine above the norm throughout the month. In total, there were 374.3 hours of bright sunshine, with the climatic norm usually at 334.1 hours. This means we enjoyed an average of 12.5 hours of bright sunshine per day last month, or roughly 1.3 hours of daylight more than the norm per day.

The brightest day of the month was the 2 June, which experienced 13.4 hours of bright sunshine, while the dullest day was the 20 June, which only saw 8.1 hours of bright sunshine. June also proved to be less cloudy than usual, with the mean cloud cover only reaching 0.6 oktas, which is less than the norm of 1.9 oktas.

With higher-than-average temperatures and brighter and longer days, June was also unseasonably dry, measuring absolutely no precipitation at all, where it usually accumulates a norm of 5.8mm.

Wind was also somewhat more diminished than usual in June with the average windspeed measuring 5.6 knots, which is lower than the climatic norm of 7.6 knots. The highest maximum gust was seen on the 4th of June, when an east-southeast wind blew at 22 knots.