The averaging period used for the following assessment was 1961-1990.
Mean temperatures generally close to or slightly above average, with the N Scotland climate area having its coldest September since 1994. Rainfall generally close to or below average, with the England SE & Central S climate area only receiving around half of the average September rainfall. Sunshine ranging from well below average across the Northern Isles to slightly above average across England and Wales.
Saughall (Strathclyde) recorded a minimum temperature of -3.6 °C on the 27th. Lee-on-Solent (Hampshire) recorded a maximum temperature of 25.4 °C on 6th.
England diary of highlights
Often fine and dry during the first half of the month. More unsettled later with rain at times, and turning colder for a while.
1st to 3rd: A weak front moved over the country on the 1st in the westerly flow, followed by drier conditions but another front swept south later on the 2nd and the wind turned north-north-westerly on the 3rd.
4th to 9th: High pressure centred west of Biscay drifted towards Ireland bringing fine and settled conditions to much of England. After a chilly start on some mornings temperatures climbed into the low to mid 20s Celsius, with 25.4 °C at Lee-on-Solent (Hampshire) and 25.1 °C at Eastbourne (East Sussex) on the 6th.
10th to 13th: A cold front pushed south on the 10th bringing rain to most parts but pressure subsequently built across the country and the fine and locally warm weather was restored.
14th to 18th: A band of rain spread south-east on the 14th followed by drier conditions on the 15th but low pressure moving north-east near Scotland drove a cold front south-eastwards across the country later on the 16th and early 17th. The fine weather returned for the 18th.
19th to 24th: The wind was predominantly south-westerly during this period and various frontal systems travelled across the country bringing rain at times. A particularly vigorous cold front brought gusts of around 60 m.p.h. on the 24th and 14 mm was recorded in one hour at Edgbaston (Birmingham). Tornadoes were reported at Nuneaton (Warwickshire) and Farnborough (Hampshire) - 36 houses were damaged in the former.
25th to 30th: The wind turned north-westerly on the 25th and pressure built over northern and western parts. A cold north to north-easterly developed for a time and maximum temperatures were well below average, typically just 11 to 14 °C in the south on 26th. Rain spread south-west across the country on the 28th, but the month ended on a drier note with lighter winds.
Wales diary of highlights
Often fine and dry during the first half of the month. More unsettled later, with rain at times, and turning colder, with temperatures below average for a time.
1st to 3rd: A weak front moved over the country on the 1st in the westerly flow, with drizzle affecting western Wales, followed by drier conditions. Another front followed south later on the 2nd and the wind turned into the north-north-west on the 3rd.
4th to 9th: High pressure centred west of Biscay drifted towards Ireland bringing fine and settled conditions. After a chilly start on some mornings temperatures climbed into the low to mid 20s Celsius inland.
10th to 13th: A cold front moved south on the 10th, bringing rain to most parts, but thereafter pressure built across the Principality and the fine and locally warm weather resumed, although with a minimum of just 2.6 °C at Sennybridge (Powys) on the morning of the 11th.
14th to 18th: A band of rain spread south-east on the 14th followed by drier conditions on the 15th but then low pressure, moving north-east near Scotland, pushed a cold front south-eastwards later on the 16th and early 17th, giving some heavy rain as it passed. The fine weather returned on the 18th.
19th to 24th: The wind was predominantly south-westerly during this period and various frontal systems crossed the area bringing rain at times. A particularly vigorous cold front brought some strong gusts on the 24th in the convective rain near its leading edge.
25th to 30th: The wind turned north-westerly on the 25th and pressure built over northern and western parts of the UK. A cold north to north-easterly airstream developed for a time and maximum temperatures were well below average, typically just 12 to 15 °C on the 26th. Rain spread south-west across mainly South Wales on the 28th, but the month ended on a drier note and with lighter winds.
Scotland diary of highlights
Near normal temperatures but drier than average, especially in the south.
Eastern areas saw good sunny spells on the 1st but patchy rain in the north-west edged south during the evening. Outbreaks of rain cleared southwards during the morning of the 2nd with sunny spells following, bringing scattered showers to northern parts. Westerly winds reached gale force across Shetland during the morning. Showers affected the north-east on the morning of the 3rd, otherwise dry with sunny spells. Cold north-westerly wind, with temperatures only reaching 11 °C in Shetland, but 17 °C in the south.
On the 4th, the north and west was cloudy with occasional rain. The south and east stayed mainly dry with some sunshine, with a temperature of 20 °C at Aboyne (Aberdeenshire) after a minimum temperature of 1.7 °C. The 5th was mainly dull in the west with some rain mainly over the north-west Highlands. Leuchars (Fife) and Strathallan (Perthshire) reached a very warm and humid 24 °C. Similar on 6th and 7th with drizzle in parts of the west and far north, but elsewhere dry with some sunshine. Temperatures reached 22 or 23 °C in the east.
On the 8th the south-east again had the driest, brightest weather with Edinburgh reaching 22 °C. The 9th saw some early brightness in the east but otherwise cloudy with showery rain spreading down from the north-west later. Showers became confined to the north during the 10th with brighter weather elsewhere. The temperature ranged from 11 °C across Shetland to 20 °C in Strathallan.
Dull across the north and west on the 11th with outbreaks of rain. The east enjoyed the best of sunshine, with Leuchars reaching 21 °C. On the 12th scattered showers affected some central and south-western areas, with the best of the sunshine over the south-east and temperatures reaching 21 °C at Strathallan. The south and east stayed mainly dry and bright on the 13th. Cloudy in the west and north with rain reaching north-west Scotland during the morning and edging south-east later in the afternoon, with strengthening south-west winds.
The 14th started cloudy with scattered showers, becoming dry with sunny periods during the day. Cold in the north, with temperatures of only 9 °C in Lerwick but warmer further south with a temperature of 19 °C at Eskdalemuir (Dumfries & Galloway). The 15th was cloudy with heavy rain across the north-west Highlands with 46 mm at Skye Lusa during the period 09-21 UTC. The rain was lighter and more patchy in the south and east.
The heavier rain transferred south-eastwards on the 16th with Eskdalemuir recording 36 mm. Brighter weather and showers following from the north-west. A cool, showery, day followed on the 17th. The 18th had a frosty start, with a temperature of -2.4 °C at Eskdalemuir. Rain, soon into the north-west, gradually extended south-east across the country. The rain was heavy at times in Argyll during the evening but lighter in the east. Another cold day, with temperatures only reaching 9 °C in Lerwick and 11 to 13 °C elsewhere.
Bright on the 19th with sunshine and scattered showers, mainly in the north-west and temperatures recovered to near average. Scattered showers overnight became increasingly frequent on the 20th and merged to give a more prolonged spell of locally heavy rain over western and central parts.
Isolated thunderstorms affected north-west Highlands and the Northern Isles. Rain moved across the south early on the 21st, clearing during the morning. Otherwise sunny spells and showers, most frequent in the north-west where they were heavy and thundery at times. The 22nd was dry and bright across the south and east of Scotland but with rain over the north and north-west. Rain moved east across Scotland during the early hours of the 23rd, clearing during the morning. Showers followed in the west, but it was mainly dry elsewhere. Heavier rain spread to the west during the evening and extended east on the 24th. Cool with frequent showers or longer spells of rain on the 25th, but drier and brighter in the southeast.
Another cool day on the 26th, with temperatures only reaching 9 °C in Aberdeen, but with showers becoming increasingly confined to the east. The 27th saw a local frost, with a temperature of -3.6 °C at Saughall (Strathclyde), followed by a bright day with sunny spells and a few light showers. The 28th and 29th were mainly dry but rather cloudy, though brighter on 29th in the north and east. The 30th was mainly dry with some bright spells. Showers developed across Argyll and extended north-east across the Highlands during the afternoon and evening.
Northern Ireland diary of highlights
Temperatures above average, with below-average rainfall.
A couple of generally cloudy days on the 1st and 2nd with patchy light rain and drizzle and just a few brighter spells. A few showers on the morning of the 3rd, otherwise dry and bright with some sunshine. The 4th started dry and bright but it became cloudy with patchy drizzle, much of it in the north and west. A mainly cloudy day on the 5th though there was a little sunshine and it became warm and humid, with several locations reaching 21 °C. Similar on the 6th with temperatures ranging from 16 °C at Ballypatrick Forest (Antrim) to 21 °C at Killowen (Down). The 7th was much sunnier in most places with Castlederg (Tyrone) reaching 22 °C.
Skies had become cloudier again by the 8th and as a result it was a few degrees cooler. The 9th brought rather cloudy skies again and the north-west saw some patchy rain later in the day, with temperatures about 17 °C at best. The rain or showers died out during the 10th to leave brighter or sunnier skies. The temperature ranged from 14 °C at Ballypatrick Forest to 19 °C at Killowen.
A grey start with occasional rain or drizzle across the north and west on the 11th, but it did brighten up at times across the south and east. The 12th was mainly cloudy but apart from an isolated shower it was dry. Quite warm with Killowen reaching 21 °C. The 13th was dry for much of the day, with sunny periods in the morning. Cloud increased through the afternoon with rain during the evening, much of it in the north.
The 14th was a bright day with some sunshine and also scattered light showers, with temperatures reaching 17 °C. Mainly dry and bright on the 15th with just a little light rain towards the north coast, with temperatures reaching 20 °C. The rain developed more widely during the morning of the 16th clearing to sunshine and showers during the afternoon, these showers becoming heavier during the evening. Ballypatrick Forest and St Angelo (Fermanagh) recorded 28 mm and 26 mm of rainfall respectively.
A cool, showery day followed on the 17th. The 18th started dry but some outbreaks of showery rain developed during the morning and continued into the evening. After a chilly start, temperatures rose to around 12 or 13 °C by the end of the day. A wet night followed with Castlederg recording 9 mm of rain. The 19th became mainly dry and bright with some sunshine, though showers returned in the evening. Quite warm with temperatures in the east reaching 19 °C. The 20th was a bright but rather cloudy day with showers. Overnight cloud and outbreaks of rain cleared away south-east by mid-morning on the 21st to leave sunny spells and scattered showers for the afternoon.
The 22nd was dry and bright with some sunshine, then cloudy during evening, with a maximum temperature of 18 °C. Overnight rain cleared on the morning of the 23rd, leaving bright spells and a temperature of 19 °C at Ballykelly (Londonderry). Moderate to heavy rain spread in during the evening. The 24th, 25th and 26th were cool with a mix of sunny intervals and showers with a brisk north or north-westerly wind, although the afternoon of the 26th was dry.
A local frost on the 27th, with a temperature of -0.5 °C at Katesbridge (Down), gave way to a fine day with sunny spells, the best of these in the west. The 28th was dry and generally rather cloudy, with a light easterly breeze and temperatures reaching about 13 °C at best. The 29th was a mostly cloudy day with patchy light rain, becoming more widespread and a little heavier in the afternoon. Temperatures again on the cool side, with a maximum only around 13 °C. The 30th was mainly cloudy with patchy light rain, dying out during afternoon. Heavier rain in the west with 18 mm at St Angelo in the period 0600 to 1800 UTC.