Diary of Highlights

1st to 5th
Much of the first half of the month was dry and warm with several days seeing temperatures in excess of 20C and up to 24C in western areas on the 4th and 5th. There were several sunny days and, apart from some thundery rain overnight on the 4th and 5th, rainfall was in relatively short supply.

5th to 14th
The thundery outbreak during the early hours of the 5th gave 15mm in two hours in parts of Co Down. Further rain or showers on the 9th and the 14th made up the bulk of the rainfall in the first half of the month.

15th to 24th
From around the 15th to the 22nd the weather was often cloudy with some interludes of showery rain. Although cooler than previously, day-time temperatures were still well up to average in the mid-to-high teens.

The first chilly night of the season occurred on the 23rd/ 24th with a widespread grass frost and a slight air frost at Katesbridge in Co Down where the temperature fell to minus 1C. For some areas, this was the first ground frost in September since 1998.

25th to 29th
The last week of the month was cool and wet and several wet spells occurred, the wettest of these being 10 -15mm on an active warm front on the 29th.

The months most dramatic weather occurred on the 28th when a very active cold front gave around 7mm of rain in less than 15 minutes in many areas. This also resulted in a small tornado at Aghalee in Co Antrim, where several homes where damaged.

The month overall was appreciably warmer than normal. By the middle of the month, mean temperatures were running around 4 degrees above average but, the cooler second half and the much cooler last week of September meant that temperatures ended about 2 degrees above the average.

It was also drier than average with most parts seeing 80 to 90% of average - thanks to the wetter conditions in the last week.