1st to 4th: A complex area of low pressure dominated the weather over the first few days of the month, initially to the west of the United Kingdom, but it then transferred east on the 3rd. There was some heavy rain and thunder across north Wales, the Midlands, East Anglia and Lincolnshire in the early hours of 1st. There were scattered thundery showers in the south-east and East Anglia later in the day. The temperature in central London reached 25.1 °C on 1st, a value not exceeded again over England and Wales until 26th. There were further thundery showers on 2nd and 3rd. An organised band of showers reached Cornwall at dawn on 2nd and spread north-east to exit north-east England in the evening. On 3rd organised thundery showers again moved from south-west England into Lincolnshire. There were showers in other parts too but south-east England stayed generally dry. On 4th a cold front cleared south-eastwards with some showery rain. It was evening before brighter skies reached the south-east.
5th to 9th: The 5th started chilly with a temperature of -0.9 °C at Redhill Aerodrome (Surrey) and a widespread grass (ground) frost across southern areas. Some rain edged south-east through the day, fragmenting overnight in southern counties. The 6th was a breezy day with sunny spells but Cornwall and west Devon were plagued by misty low cloud and some drizzle. Some showery rain spread into northern districts later. This rain cleared the south overnight, but not before giving some heavy rain in places, as a small low centre tracked south-east to be in the southern North Sea by the morning of the 7th. All parts then had a rather cold and breezy day with sunny spells and showers on 7th with some thunder and hail. A gust of 45 knots was recorded at Holbeach (Lincolnshire). There were further showers on 8th and 9th, again with hail and thunder in places. Benson (Oxfordshire) recorded -0.3 °C on the morning of the 8th. South-west England, the south coast and south Wales stayed mainly dry.
10th to 15th: Pressure rose during the 10th. There were some showers across eastern counties as a trough spread south. By 11th the high was established, giving many areas a couple of dry and largely sunny days. There was widespread ground frost early on 11th with an air frost in a number of places. Woburn (Bedfordshire) recorded -3.1 °C. Pressure was falling to the south and a chilly easterly wind picked up especially across southern England. Culdrose (Cornwall) recorded a gust of 41 knots on both 12th and 13th and the temperature only reached 10.0 °C at Cromer on 13th. Some rain edged into Cornwall and Devon on 13th and patchy rain spread to other southern counties as far east as East Sussex on 14th. There was a frost in some places again early on 15th, with -2.3 °C recorded at Benson. There was further rain over south-west England whilst northern England and north Wales had a sunny day.
16th to 18th: Rain spread south on a cold front on the 16th. There were some showers across north Wales in the morning on 17th and north-east England by afternoon. A short-lived ridge of high pressure brought a fine day to many on 18th but rain spread into south-west England and south Wales later.
19th to 23rd: Low pressure dominated the weather through this period. Rain in the south-west early on 19th spread to most places by dawn. Drier, brighter weather developed in the west but southern counties had some heavier rain by evening. The south still had some rain in the morning of the 20th. Heavy thundery showers developed from south-west England to north-east England and East Anglia. It was warm in the east with 20.5 °C at Coningsby (Lincolnshire). There were further showers between 21st and 23rd. A tornado was reported at Heachem (Norfolk) on 21st. On 23rd it was showery especially in the west and north. Shap Fell (Cumbria) recorded 19.6 mm of rain 0900 to 2100 UTC whilst more south-eastern parts of England were largely dry and bright.
24th to 27th: Fronts spread some rain eastwards on 24th but most places brightened up in the afternoon. Western and southern coasts had misty low cloud and some drizzle on 25th as a warm front moved north-east but it gave very little rain elsewhere. A weakening cold front in the west on 26th cleared the south-east in the evening and then another warm front moved north on 27th. Warm southerly winds on 27th gave a hot day to most parts. In central London the temperature reached 31.9 °C, the highest May temperature in the UK since 31st May 1947. There were some thundery showers across central southern England in the morning and these spread north to north-east England in the afternoon.
28th to 31st: A cold front brought fresher weather on 28th and strong winds especially to the west. Capel Curig (Gwynedd) recorded a gust of 54 knots. It was dry with sunny spells in most parts but especially the east. Winds were lighter the following day and most places were dry. An area of heavy rain over the far south-east and East Anglia overnight and early on 30th gave 16.4 mm of rain at Wattisham (Suffolk) in the 12 hours to 0900 on 30th. Showers developed in many places during the morning but especially the east. These were heavy and thundery in places and tornadoes were reported around Soham (Cambridgeshire) and Newmarket (Suffolk) in the late morning. There were a few showers on 31st to round off the month.
