September Days – warmest in the past six years

Malta Independent Tuesday, 2 October 2007, 00:00 Last update: about 20 years ago

It was very dry and the weather was slightly warmer than normal in September, the Meteorological Office reported yesterday.

With an average temperature of 28.8°C, September days were warmer than average by almost half a degree. The warmest day last month was the 19th, when the temperature at Malta International Airport peaked at 33.7°C, and the coolest was the 25th, with a high of only 25.9°C. The hottest September days on record were those of 9 and 10 September 1924, when a temperature of 38.9°C was reached.

The nights last month were also warmer than average by 0.7 of a degree, with the warmest night being that of the 27th when the temperature persisted at 24°C. The least warm were those on the 6th and 9th when the thermometer dipped to 17.9°C. Records at the Malta International Airport show that the least warm September night occurred on the 21st in 1969, with a minimum of 13.2°C.

The Meteorological Office also keeps a record of the temperature at grass height level. Last month’s lowest temperature at that height was 14.3°C; this was a good two degrees warmer than the norm. Since 1922, the coolest it ever got at grass height in September was 7.3 °C and this was on the 28th in 1979.

September is widely, and very wrongly, perceived as the most humid month of the year – in fact there are seven months that are more humid, the worst two being December and January.

Last month was in fact one of the driest on record – only one other September in the past 30 years, that of 2004, was drier. At 71 per cent, last month’s average values of Relative Humidity were lower, by five percentage points, than the average of the past 30 years.

The sea temperature last month was 25.9°C, slightly more than half a degree warmer than the average for the month.

A total of 30.2mm of rain fell last month at the airport – the average rainfall in September being 49.9mm. The wettest day was the 25th, with 23.8mm measured during a thunderstorm at the airport, and more than twice this amount (48.8mm) at Xewkija. The wettest September on record was that of 1997, with 266.9mm, and the driest was that of 1943, which was a completely dry month.

Thunder was heard on one day last month. This is about a third of the average for September. The stormiest September was that of 1955 with 11 days followed by that of 2003, with 10 thunderstorm days.

As for the wind – The Summer Wind, as Frank Sinatra and Julio Iglesias would refer to it – last month was quite a lively one, with almost one in four days being in the moderate to rather strong bracket. The average speed was 7.3 kts (8.4mph or 13.5 kilometres an hour) and the most frequent direction was the West Northwest. The 25th registered the strongest gust of the month – 34 knots (39mph or 63 kilometres an hour), from the East Southeast.

There was on average eight hours and 18 minutes of sunshine a day, which means that last month there was a total of just six hours of sunshine fewer than for an average September.

The sunniest day was the 2nd, with 11 hours and 36 minutes, while the dullest was the 25th when, after a rainy start, the sun shone brightly for only three hours and 36 minutes.