General and Barometric Pressure

  A cold and wintry start to the month was quickly replaced by a much milder and wet regime; becoming quite unsettled and windy in the second half of the month.

  MSLP of 1006.7 Mb was -2.9 MB below average for the month and after a very calm first half of the month, the second half was quite disturbed and often windy. Those winds often came over the top of high pressure sat in the Atlantic on a strong westerly and several days saw gusts exceeding 50 Mph.

  The start of the month saw a continuation of the cold conditions experienced at the end of November. This brought a number of sharp frosts and with very low maximum temperatures on the 1st and 2nd. Indeed the 1st was especially cold both by day and night, a minimum overnight temperature of -7.8°c was then followed by an 'Ice Day' when the thermometer remained below zero for the entire 24Hrs with a maximum of -0.3°c; however, it was a gloriously sunny day.

  For the south of the county the 2nd would then see the most significant snowfall since 2010, but further north and east in our part of the county, whilst the snow fell consistently during the day, it only managed a depth of 4cms. However, with the cold conditions that snow was still laying on the ground 3rd and 4th. Another sharp frost along with a sunny day would follow on the 6th, but now a milder regime would begin to dominate, and up to the 13th, a wetter one.

  Low pressure (LP) would now dominate and any incursion of high pressure (HP) would be transitory and thus brief. The 7th would be the month's wettest day (just) with 34.2 mm on what was a really grim day; after a wet morning the rain really got going in the afternoon and at times was heavy. LP was sat just to the west of Eire and the next few days saw the rainfall totals stack up: 11.2 mm (8th), 8.9 mm (9th) and 12.9 mm (10th) when a new area of LP moved quickly across the UK from the west. During this wet period, day-time maxima were slightly above the seasonal average, but on an upward curve.

  The pressure gradient did then slacken, but still with a little rain 11-13th, but also some sunny intervals, before a ridge of HP nudged in 14-16th. However, apart from a slight frost 14th, it actually became milder and started a trend of day-time maxima often being in double figures.

  Rainfall totals 14-25th were actually insignificant but now the majority of the days were really quite windy; gusts exceeding 50 Mph were recorded on 17th (56 Mph), 21st (54 Mph) and 28th (53 Mph) and with a mean wind speed of 24.1 Mph became the windiest day of the year.

  Temperatures during this period were well above average, but with that wind it didn't always feel that mild. The 23rd (12.8°c) and then a month's high of 13.0°c on the 24th being especially mild and which included an overnight minimum of 9.6°c into the 24th - but with all this mildness came a frequent blanket of cloud and overcast skies.

  And then after this relative lull in daily rainfall totals came the 27th. Rain of 12.8 mm overnight was credited back to the 26th, but it also rained all day, was occasionally heavy, to give a final total of 34.1 mm. The 28th wasn't much better as a series of trough lines pushed through to bring a number of heavy showers; but with rain from 11-13h which at 1235h became somewhat violent and included hail and that wind gust of 53 Mph.

  The final two days of the month saw a new and deep area of LP from the west that moved east across Cumbria. Consequently there was no let up in the wet conditions with rainfall totals of 14.4 mm (30th) and 6.7 mm (31st). However, it had become that little bit cooler, a slight air frost being recorded on the 30th in the transition between frontal systems.

  Temperature

  With a mean minimum of 2.74°c and a mean maximum of 8.01°c December 2023 saw the temperature 1.48°c above the fourteen year average for this site. This saw it being the warmest December since 2016 and since the record commenced (2009), three have been warmer and eleven colder.

  The 'Ice Day' on the 1st was the only one recorded during 2023 and after the 6th only four more days would see maxima below the seasonal average. The period of 15-25th was exceptionally mild by both day and night, but especially by night.

  At the Met' Office site at Shap a mean minimum of 2.1°c and a mean maximum of 7.6°c saw the monthly mean temperature 1.65°c above average. It was the warmest December since 2018 and since the record commenced (1992), four have been warmer and twenty-five colder (no data in two of the years).

  Precipitation

  At Maulds Meaburn rainfall in December totalled 185.0 mm (7.28 In), this being 117.0% of the average for 2007-22, making it the wettest December since 2015. And since the record commenced (2007), thirteen have been drier and three have been wetter.

  The snowfall on the 2nd amounted to a total of 7.9 mm and from the 16th rain was recorded on every day. However, with only light rainfall and strong winds during the period 13-24th the ground had begun to dry somewhat, but by the month's end was once again saturated.

  Locally rainfall at Maulds Meaburn North was 199.9 mm and at Castlehowe Scar 243.3 mm. At the Met' Office site at Shap, rainfall of 317.0 mm represents 129.3% of its average making it the wettest December there since 2015. And since the record commenced (1989), twenty-eight have been drier and six wetter.

  Figures from the Environment Agency's rainfall sites were, (figure in brackets being the monthly average for 1991-2020)   'Data kindly provided by the Hydrometry and Telemetry team of the Environment Agency (Penrith)':

  At Appleby in Westmorland rainfall of 153.9 mm (LTA of 96.9 mm) represents 158.8% of its average (1856-2022) and made it the wettest since 2015 - since the record commenced, 148 have been drier and 19 have been wetter.

  Kirkby Thore 137.6 -- (91.8 mm)

  Haresceugh Castle (Kirkoswald) 139.57 mm -- (108.6 mm)

  Brothers Water 580.66 mm -- (354.3 mm)

  Seathwaite Farm (Borrowdale) 666.2 mm -- (390.9 mm [average for 1845-2022]) - making it the wettest since 2015 and since 1845 when the record commenced, 13 have been drier and 165 have been wetter.

  OTHER:-

  During the month the following 'days of' were recorded: snow and hail fell on one day each with snow laying on the ground (to a depth of 1cm at 09h) on two days -- the wind speed averaged 7.58 mph, with a maximum gust of 56 mph (17th) with gusts of 50 Mph or more recorded on three days.

  We had 8 Air Frosts in the month (year 49)          --          Grass Frosts totalled 13 (year 104).

  The 1 foot soil temp ranged from a low of 3.5°c on the 3rd and 7th        to      a high of 8.0°c on the 24-25th     --      with a monthly mean of 5.9°c

  The 1 meter soil temp ranged from a low of 7.2°c on the 9th      to      a high of 8.8°c on the 1st     --     with a monthly mean of 7.9°c

   This makes the year of 2023 0.82°c warmer than the average for 2009-22 and with 108.9% of average rainfall for 2008-22

  Cumbrian Rainfall

  This was broadly the wettest December since that of 2015 (but will any month of any name ever be wetter?), yet at two stations the final total for the month managed to finish below average. And these two stations, Seaton (Workington) and Whinfell (Oasis) have no geographical connection, but came in just below the norm'.

  However, percentage falls were above average across the county, although by varying degrees, some of which was virtue to the snow event of the 2nd which had the greatest impact in the south of the county. During this event, Palace Nook (Barrow) saw a 'precipitation' total of 44.8 mm, whereas at many other stations the two day total was in the low single figures.

  Only here and at neighbouring Walney Island the was the 2nd the month's 'wettest' day - it should be raised as a possibility (probability) that with the amount of snow that did fall, that some of this would have been lost from the final total and that at some stations it wasn’t registered until several days later as it melted.

  The highest percentage fall for the month would be found at Palace Nook and which was the only site to top the 200% mark; Walney falling just short of double its average.

  The 7th was more broadly the first widespread wet day across the county with the period through to the 13th having some high daily falls. By this time the ground was truly saturated. More in the east of the county it was then fortunate that the period through to the 23rd only saw nominal falls and was coupled with a turn to much windier conditions that saw the ground dry appreciably. However, and it is a big 'however' - to both south and west, but especially in the LDNP, this period still saw some high daily falls, the wettest of which was the 17th.

  At some locations this was the wettest day of the month (Ennerdale Black Sail returning 110.4 mm for the highest 24hr total of the month), yet to the east of Penrith only 1.0 mm was recorded at Kirkby Thore.

  The final week of the month became increasingly wet, the 27th being the month's wettest day at the majority of sites. It's curious that at the three sites of Honister, Seathwaite and Mickleden, which are geographically extremely close to each other, their wettest day of the month was different at each one. Mickleden would return the months highest total (722.2 mm - 28.42In) and like Honister would record an inch or more on nine days in the month, but at Honister five days would exceed 50mm to Mickleden's four.

  Impacts - notable at the beginning of the month (2nd), especially in the south of the county, due to snowfall. Major disruption to travel as Cumbria police declared a major incident and warned people not to travel. Thousands of homes and businesses were left without power and hundreds of motorists became stranded.

  Snow - as 'impacts' above - there were unconfirmed reports of more than 12in (30cm) of snow in some places in the south of the county.