Month: January 2025

Friday yet again was a very cold day under the very light easterly air stream although we enjoyed a few hours of welcome sunshine. The thermometer eventually reached a maximum of just 1.9C at 14.18 being 5.2C below my 40-year average. From that time the thermometer began to slowly fall away reaching freezing again, taken as -0.1C, at 18.06, even earlier than on Thursday. The minimum of -7.5C, due to the clear sky overnight with no cloud to provide a duvet to minimise any loss of warmth, was logged at 07.17 early Saturday being once again a significant below average temperature at -8.8C. Friday was dry with little air movement, sometimes calm for many hours, with my anemometer registering the strongest air movement of just 8mph on one occasion.

Saturday after first light revealed the sky was still clear with the temperature at 08.00 having recovered slightly to reach -6.9C.

Automatic rain gauges are great for live monitoring of precipitation but not accurate on timing when snow or sleet falls. After a snow event I bring in my Met Office type copper rain gauge at 08.00 and slowly melt the snow before measuring accurately. With near freezing weather during many hours, as we have experienced this week, any snow in an automatic rain gauge will only melt under the influence of sunshine or when the temperature recovers significantly thus it will only register the precipitation slowly many hours later or even days after the event.

The centre of the high pressure today will leave Scotland and emigrate to England and continue the calm conditions and dry weather, with sunshine. The warmer air has begun to spread over the West Country and will slowly move eastwards with Sunday in Marlborough being cool, but thankfully not so cold as the past week and on Monday closer to average.

The Jet Stream is on course to arch to the north of the UK from Sunday thus leaving the UK on the warmer southern side thus cutting off the flow of cold air

Although there was welcome sunshine on Thursday the cold air, on a light northerly airstream, meant the thermometer struggled to reach a maximum of 3.2C being 3.8C below the average but at least it was a couple of degrees higher than on Wednesday. Under clear skies for much of the night the thermometer slowly fell reaching a minimum of -7.2C at 05.40 early Friday. It was the coldest night since 24th January 2023 (-8.0C) and a significant 8.5C below my long-term average. It became clear that it was going to be a colder night as the thermometer dropped to freezing (-0.1C) at 21.10 on Wednesday evening but at a much earlier time on Thursday at 18.44.

Cloud was seen encroaching after first light that allowed a slight recovery in the air temperature to read -5.7C at 08.00. The barometric pressure has been rising again having risen 12mb since Thursday as the anticyclone centre is currently between us and Iceland that will produce a calm day with a light easterly flow of air today as it produces a ridge down over the country.

The cold days and nights have meant the chill has been seeping into the ground. The temperature of the soil at a depth of 5cm at 08.00 has read 5.8C, 1.6C and 0.7C for the previous three days respectively but today read -1.1C at 08.00.

There are two warm weather fronts lurking off the cast of Cornwall but the high pressure is stopping them moving eastwards to bring warmer air. The Jet Stream is still to the south of the UK and won’t arch to the north, putting us one the warmer, south side until later on Sunday.

2024 Annual Survey

Maximum Day Temperature 30.7 19th July
Minimum Day Temperature 0.7 19th December

Maximum Night Temperature 18.1 2nd December
Minimum Night Temperature -6.3 19th January

Last Air Frost – Spring -0.7 25th April
First Air Frost – Autumn -0.4 11th October
Number Air Frosts 28

Total Precipitation 1126.8
Maximum Daily Rainfall 43.4 23rd September

No. Days with Snowfall 1
No. Days with Thunder 4
No. Days with Small Hail (<5mm) 5 No. Days with Large Hail (>5mm) 0
No. Days with fog at 08.00 25

Soil Temperature (av at depth at 5cm) 10.3
Max Soil temperature at 5cm depth 22.2 1st August
Min Soil temperature at 5cm depth -2.9 19th January

Wettest Month 221.4 September
Driest Month 25.0 June

Maximum Wind Gust 45 7th December

Maximum Barometric Pressure. 1040.0 11th January
Minimum Barometric Pressure 976.1 2nd January

Wind Directions
20 N
34 NE
22 E
29 SE
47 SE
87 SW
80 W
47 NW

N.B. Temp in C: Rainfall in mm: Wind Speed in mph: Barometric Pressure in mb

Temperatures continued to fall on Wednesday as the Arctic air was still in place along with total cloud cover that prevented any sunshine, however weak. The thermometer eventually struggled to a maximum of 0.8C at 14.56 and stayed there until late evening, this low being a significant 6.3C below my 40-year average. The two weather fronts that had been lurking off the coast of France and the English Channel decided to move northwards across Southern England in the afternoon, the cloud thickened with the first light drizzle and sleet observed at 16.00 that initially triggered the automatic rain gauge with 0.2mm but as the temperature dropped and more consistent snow began to arrive at 17.50 the moisture began to freeze.

The total melted precipitation amounted to 1.2mm.

First light on Thursday saw the remnants of the cloud from the two weather fronts disappearing over the eastern horizon that had kept the overnight low to around -0.5C, which then dropped to -1.5 by 07.00 and -2.9C at 08.00 under clear skies.

The wind direction has changed from an easterly to north-west today, and later west, that will continue to feed cold air over the UK being directed between a depression over Scandinavia with air circulating anticlockwise and an anticyclone in the Atlantic with air circulating clockwise. The thermometer eventually fell to -3.3C at 08.46 and any further drop arrested by the arrival of weak sunshine.

2024 Annual Survey

Maximum Day Temperature 30.7 19th July
Minimum Day Temperature 0.7 19th December

Maximum Night Temperature 18.1 2nd December
Minimum Night Temperature -6.3 19th January

Last Air Frost – Spring -0.7 25th April
First Air Frost – Autumn -0.4 11th October
Number Air Frosts 28

Total Precipitation 1126.8
Maximum Daily Rainfall 43.4 23rd September

No. Days with Snowfall 1
No. Days with Thunder 4
No. Days with Small Hail (<5mm) 5 No. Days with Large Hail (>5mm) 0
No. Days with fog at 08.00 25

Soil Temperature (av at depth at 5cm) 10.3
Max Soil temperature at 5cm depth 22.2 1st August
Min Soil temperature at 5cm depth -2.9 19th January

Wettest Month 221.4 September
Driest Month 25.0 June

Maximum Wind Gust 45 7th December

Maximum Barometric Pressure. 1040.0 11th January
Minimum Barometric Pressure 976.1 2nd January

Wind Directions
20 N
34 NE
22 E
29 SE
47 SE
87 SW
80 W
47 NW

N.B. Temp in C: Rainfall in mm: Wind Speed in mph: Barometric Pressure in mb

After waking to a surprise covering of snow on Tuesday, from a passing shower just before dawn, the thermometer struggled to climb to a maximum of 4.7C at 13.36 even though we enjoyed many hours of sunshine that lasted through to the afternoon. This high was 2.4C below my long-term average and outside it felt a couple of degrees cooler than indicated on a thermometer due to wind chill. It was a dry day and the UV light gave a value of 0.6 on the sensor.

The past night saw the thermometer slowly fall away to a low of -2.7C at 05.41 early Wednesday being a significant 4.0C below average.

Wednesday after first light revealed a sky with total cloud cover that had allowed the temperature to make an about turn, after the early clear skies, to rise a little to -2.2C by 08.00.

Two warm fronts are lurking over Brittany being associated with a new depression over Biscay. The centre of the low will move eastwards over France and during the daytime the fronts will ease northwards towards Southern England with possible precipitation alert in the day or evening. This low has meant the wind backing from the west yesterday to east today and then probably northeast later in the day so another very cold day ahead.

The soil temperature at a depth of 5cm read 0.7C at 08.00 due to the nighttime frost and still some lingering snow in the shade from the sunshine on Tuesday.

There are signs that the Jet Stream will move north of the UK on Saturday. This change in direction will begin to cut off the flow of cold air from the north, the UK then being on the slightly warmer, southern side, which will mean temperatures recovering to near normal for January from Sunday.

Under cloudy skies and a brisk westerly breeze the temperature on Monday eventually rose to a maximum of 5.7C at 13.46 being 1.4C below average. This below average temperature was not unexpected as the ground was still very cold from the Arctic air of previous days, there was no sunshine to lift the temperature and the cold air from around the Arctic was still in place. I deduce that the snow which was evident at daybreak on Tuesday fell in the early hours as the 5 minute radar showed a very red, angry display reaching our area at 06.10 and clearing at 06.35. The level snow depth was just 1cm that on melting amounted to 1.4mm of precipitation for the last twenty-four hours.

The thermometer fell to a minimum of 0.1C at 05.02 early Tuesday and lifted to 0.8C by 08.00 thanks to the cloud arriving at 06.10 that brought the snow minimising any further loss of warmth into the atmosphere in a previous relatively clear sky. The soil temperature at a depth of 5cm read 1.6C at 08.00.

The deep depression is very slowly easing eastwards towards Scandinavia but will still direct the cold air, originating from the north, on a westerly air stream. The barometric pressure has risen a significant 22mb over the last twenty-four hours with a reading of 997.9mb at 08.00.

We will still be on the cold north side of the Jet Stream until it is projected to move later in the weekend when it might get a little warmer

P.S. The 2025 Data Stats is now online.