The averaging period used for the following assessment was 1961-1990.
A very sunny month across the whole of the UK, with many stations breaking their sunshine records. Most of the country received less than average rainfall, with parts of England and Wales only receiving a third of average. Temperatures were close to average over Scotland and Northern Ireland, but nearly a degree below normal over England and Wales.
Temperatures reached 16.1 °C in North Wales on the 11th. There were severe frosts during the month, with temperatures falling as low as -11.6 °C at Tulloch Bridge on the 31st.
England and Wales diary of highlights
Dry and very sunny especially in the south. Mild at first but colder later with widespread frost. There was snow in a number of areas from the 22nd. A white Christmas in some places.
1st to 5th A mostly mild unsettled start to the month as Atlantic fronts crossed the region. Wet weather on the 3rd heralded more of the same during the 4th/5th as a low-pressure system moved east over northern England. The rain turned showery and heavy at times on the 5th.
6th to 11th With high pressure firmly established over the region, a dry, mostly sunny regime prevailed. It was mild at first especially around western coastal areas, however temperatures elsewhere later slid into the rather cold category. There was some rain and drizzle around western coasts at first, otherwise many places had patchy mist or fog and some overnight frost. Where fog persisted in the Midlands and north-east England it stayed cold. Some western areas stayed mild, with Nantmor/Gwynedd reaching 16.1 °C on the 11th.
12th to 18th The anticyclone migrated northwards allowing a light easterly flow in the south. It continued very dry and generally sunny at first, but rather cold with fairly widespread frost at night. Cloud increased later with patchy rain and drizzle from the 15th to the 17th.
19th to 26th Changeable with some snow in places as deep depressions moving south-south-east from the Norwegian sea brought cold northerly outbreaks. The first of these on the 21st /22nd brought snow showers to east coast counties as far south as north Essex, giving 2 to 5 cm in places. The second outbreak on Christmas Day brought snowfalls to North Wales especially on high ground. More snow showers fell in the north-west on the 26th.
27th to 31st A vigorous low near Iceland on the 27th moved south-east to Denmark by the 28th deepening rapidly as it passed Scotland. Strong to gale NW winds brought progressively colder air from the Iceland/Greenland area, with many places receiving significant accumulations of snow by the 29th/30th. St Bees Head (Cumbria) had a gust of 68 kn on the 28th. A weather band gave substantial snow over high ground in extreme south and south-west England early on the 29th, with some on low ground also, parts of Sussex receiving 2 to 3 cm. Widespread frost, severe at times, developed later, with Sennybridge/Powys falling to -10.9 °C early on the 31st..
Scotland diary of highlights
Dry and sunny.
A large and intense anticyclone dominated Scotland's weather for the middle fortnight of December. It started life over eastern Europe and moved slowly west to the Atlantic, giving dry weather with variable amounts of cloud. During the first week a changeable westerly regime prevailed, while the last 10 days saw northerly winds become established.
The weather during the first week was varied, with rain and gales during the night of 3rd/4th followed by rain in the south on the 5th. More rain reached the north-west on the 7th. Between these rainfall events there was much bright weather with broken cloud and some showers.
The large anticyclone first influenced Scotland's weather on the 7th and 8th by directing a very mild southwesterly airstream across the country, and the temperature at Lochcarron reached 14.4 °C. As the anticyclone approached Scotland, dry continental air spread north, bringing clear skies that gave cold nights inland from the 9th to the 13th.
Cloud spread from the east on the 13th and the period when the anticyclone was closest to Scotland was associated with generally cloudy skies. As the high continued its westward movement away from Scotland, breaks in the cloud appeared on the 17th and 18th.
The remainder of December was characterised by outbreaks of cold northerly winds alternating with milder air associated with depressions moving south-east from Iceland. The first snow showers arrived on 21st December, and on Christmas Day there was snow lying in the north-east, with light snow flurries further south. The most intense of the depressions brought gales during the early hours of the 28th, with a gust of 74 kn at Barra, while blizzards affected northern districts. By the 31st over 20 cm of snow lay over much of northern Scotland and the temperature at Tulloch Bridge fell to -11.6 °C.
Northern Ireland diary of highlights
Dry and very sunny.
1st to 6th A rather cold but sunny start to December on the 1st, otherwise quite mild. Widespread persistent heavy rain fell on the 3rd and 4th giving combined daily totals of between 21 and 50 mm for the two days which equated to between 50 % and 80 % of the total monthly rainfall recorded.
7th to 18th Widespread ground frosts occurred throughout much of this period, locally severe on the 12th and 15th. Little or no rainfall was recorded anywhere during this period. It was very sunny from the 9th and 13th inclusive and again on the 17th. Around half of the total sunshine duration for the month were recorded on these days alone. The 7th was the warmest day of the month everywhere with the highest maximum temperature of 14.5 °C being recorded in the Lagan Basin area.
19th to 28th Air temperatures frequently fell below freezing and widespread ground frost, some locally severe, were recorded throughout this period. Only small amounts of rainfall were recorded between the 19th and 23rd. Moderate to heavy rain and showers, some wintry in nature, fell on 24th, 25th and 26th. It was very sunny in most places on the 22nd.
29th to 31st Predominantly cold with heavy snowfalls on the 29th followed by air temperatures below freezing and widespread ground frost, some locally quite severe. This meant that by 31st snow was still lying in many areas causing hazardous conditions to pedestrians and motorists.