Category: Monthly Reviews

                                                                      Rather Dry

Temperatures

The average maximum temperature during November 2024 in Shoreham was 11.4 Celsius (52F), and that was close to the long-term average, but 0.5 Celsius (<1F) below average for the last 10 years. The average minimum temperature was 7.0 Celsius (45F), and that was  1 Celsius (<2F) above the long-term November normal, but average for the last 10 years.

The highest temperature recorded during the month was 16.2 Celsius (61F) on the 24th, but this was the only maximum temperature above 15 Celsius (59F). A high of 14.2 Celsius (58F) occurred on the 1st, and a further 9 days had maxima above 13 Celsius (55F), with 6 of these milder days occurring before mid-month. Most other days (14) had maxima ranging from 10 to 13 Celsius (50-55F). On 2 of the remaining days, the 9th and 28th, maxima were between 8 and 10 Celsius (46-50F), but there was the briefest of cold snaps. The 4 days commencing on the 19th each had highs below 8 Celsius (46F), with 3 of these having maximum temperatures under 6 Celsius (43F).  A high of 5.4 Celsius (41F) was recorded on the 19th, and 3.8 Celsius (39F) was measured on the 21st.       

There were no exceptionally mild nights during November, but the temperature only fell to 13.2 Celsius (56F) on the 24th, with 12.4 and 12.2 Celsius (54F) measured on the 1st and 3rd respectively. A further 4 nights had minima above 10 Celsius (50F), with 3 of these milder nights occurring during the first week of November. On most other nights (15) the minimum temperature ranged from 5 to 10 Celsius (41-50F), but there were some colder nights, with all of these occurring after mid-month. On 6 nights the temperature dipped below 2 Celsius (36F), with first of these colder nights occurring on the 16th, and the last one on the 28th. The coldest nights occurred between the 20th and 23rd with the lowest temperature of minus 1.4 Celsius (29F) occurring on the 22nd.   

The sea temperature decreased steadily from 15 Celsius (59F) at the beginning of November to 11 Celsius (52F) at the end of the month.

 

Frost

 

There were 3 air frosts in November, all of them slight. The temperature fell to minus 1.1 Celsius (30F) on the 20th, minus 0.6 Celsius (31F) on the 21st, and minus 1.4 Celsius (29F) on the 22nd. The 23rd just missed an air frost with a low of 0.2 Celsius (32F). There were 7 grass frosts during November. The first of these occurred on the 16th, when minus 2.2 Celsius (28F) was recorded. The 26th and 28th each had grass minima of minus 1.1 Celsius (30F), but the lowest grass temperatures occurred between the 20th and 23rd. Each night had a temperature of minus 3.9 Celsius (25F) or lower, with minus 5.6 Celsius (22F) occurring on the 22nd. 

 

Rain

 

Rainfall during November amounted to 76.2  millimetres (3 ins.), which was around 15% below the long-term average, but 30% below the short-term average. Measurable rain fell on 12 days, which was 5 days below the average, and wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 10, which was 3 days below the average.  The first half of November was very dry, with only 0.2 millimetres (0.01 ins.) of rain measured. This fell as drizzle on the 6th. The dry spell was characterised by extremely dull weather. For example, at Charlwood (near Gatwick Airport) no sunshine was recorded between the 31st October and 11th November, a total of 12 days. The anticyclonic gloom then lifted, but after mid-month it turned unsettled. The 28th was the only completely dry day after the 16th, but even so, much of the rain was light, with only 4 days registering daily falls above 4 millimetres (0.16 ins.). Steady rain in the afternoon, evening and overnight on the 18th produced 18.0 millimetres (0.71 ins.). Wet weather on both the 23rd and 24th, gave 8.2 millimetres (0.32 ins.) and 14.0 millimetres (0.55 ins.) respectively. Heavy overnight rain was the main contributor to the 24.6 millimetres (0.97 ins.) that made the 26th the wettest day of the month.  

 

Hail

No hail was observed in this part of Shoreham during the month.  

 

Thunder

There was just 1 rumble of thunder heard in this part of Shoreham during October. This was late in the evening on the 8th.

 

Snow

 

Flakes of snow were briefly observed amongst the rain around mid morning on the 21st.

 

Wind

 

November was an anticyclonic month overall with the mean pressure over 8 millibars above average. With the high pressure centres mainly over, or to the west of,  the British Isles, the dominant winds were from between northwest and northeast, with these directions accounting for over two thirds of the daily oibservations. In fact, dominant winds from a southwesterly direction only occurred on 3 days, all of these in the second half of the month. Winds were mainly light or gentle until the end of the third week, but they were stronger at times thereafter, especially during the fourth week of November. At Shoreham Airport, a brief interlude of southwesterly winds gusted to 34 knots (39 mph) in the early hours of the 19th, with southwesterly winds producing a very windy day on the 23rd. Gusts in excess of 40 knots (46 mph) were frequent during the day, with several gusts reaching 45 knots (51 mph) in the late afternoon and evening. The wind generally decreased in strength after midnight, but gusts from the southwest continued to exceed 30 knots (34 mph) throughout the 24th, with peak gusts of 41 knots (47 mph) around mid-morning. The last gusts of the month above 30 knots (34 mph) occurred early on the 27th, with southwest winds responsible for gusts of 31 knots (35 mph).

 

 

Fog

 

There was no fog in this part of Shoreham, but webcams suggested that fog shrouded the hills at times early in the month.

 

Statistics for November 2024

 

Reporting Site	Highest Temp	Lowest Temp	Rain Total (mm)	Wettest	Rain days
Shoreham A/P	16.2	-2.3			13
Thorney Island	15.9	-0.5			12
Gatwick A/P	16.7	-2.5			13
Herstmonceux	16.6	-2.1			15
Bournemouth (Hurn)	16.6	-3.9			12
Middle Wallop	16.5	-2.9			12
Dieppe	14.0	1.4	38	20	8

• Rainfall totals unreliable for all English stations

                                                Rather Dry and Warm

Temperatures

The average maximum temperature during August 2024 in Shoreham was 22.6 Celsius (73F), and that was around 2 Celsius (3.5F) above the long-term average, but near average for the last 10 years. In fact,  average  day-time temperatures this August were the 14th highest in the area since 1880. The average minimum temperature was 15.0 Celsius (59F), and that was around 1 Celsius (<2F) above the August normal, but more than 2 Celsius (3.5F) above the long-term average. Nights during August were the 8th warmest in the area since 1880.    

The highest temperature recorded during the month was 27.9 Celsius (82F) on the 11th, but 26.7 Celsius (80F) was recorded on both the 1st and 12th. The only other day when the temperature exceeded 25 Celsius (77F) was on the 28th, when 25.2 Celsius (77F) was recorded. On most other days the maximum temperature ranged from 20 to 25 Celsius (68-77F) with only 2 exceptions. On the 22nd a high of 18.4 Celsius (65F) occurred, but the coolest day of the month was the 24th,  when the temperature only reached 18.1 Celsius (64F).      

There were several warm nights during August, and the minimum on the 12th was 21.7 Celsius (71F). This was only 0.1 Celsius (<0.2F) below the August record set in 2020. Minima between 18.0 and 18.2 Celsius (64-65F) occurred on 4 nights, all before the 10th; and a further 4 nights had lows above 17 Celsius (63F). On many nights (14) the minimum temperature was between 12 and 14 Celsius (54-57F), but on 3 nights, the 7th, 19th and 25th, the temperature fell below 12 Celsius (54F). The coolest of these nights was the 25th, with a low of 10.9 Celsius (52F).   

The sea temperature was 19 or 20 Celsius (66-68F) throughout the month.

 

Frost

 

There were no frosts in August. The lowest grass temperature was 7.2 Celsius (45F),  on both the 19th and 25th. 

 

Rain

 

Rainfall in August amounted to 47.8 millimetres (1.88 ins.), which was around 25% below the monthly average. Measurable rain fell on 7 days, which was 6 days below the average, and wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) also numbered 7, which was 2 days below the average. No measurable rain fell during the first 5 days of August, but rain and drizzle produced 1.8 millimetres (0.07 ins.) on the 6th, and heavier rain and drizzle gave 6.6 millimetres (0.26 ins.) on the 8th. It was heavy drizzle and rain that added 8.4 millimetres (0.33 ins.) on the 15th. There were only 3 days with measurable rain during the first 3 weeks of August, but then the remainder of the month’s rain fell in 4 days. Drizzle was mainly responsible for the 4.8 millimetres (0.19 ins.) that fell on the 22nd, but heavy rain overnight and during the morning of 24th gave 15.4 millimetres (0.61 ins.) and 7.0 millimetres (0.27 ins.) on the 2 ‘rain days’ (0900-0900 UTC): the 23rd and 24th respectively. Showery bursts of rain on the 25th completed the total for the month with 3.8 millimetres (0.15 ins.). 

 

Hail

No hail was observed in this part of Shoreham during the month.  

 

Thunder

No thunderstorms were observed in this part of Shoreham during the month.

 

Snow

 

No sleet or snow was observed in Shoreham.

 

Wind

 

August was very much another southwesterly month with winds from that quadrant blowing on over 70% of the days. Other days were more variable, but at the end of the month there were 2 days when northeasterly winds dominated. Winds were mainly gentle or moderate, but quite strong at times during the third and fourth weeks. At Shoreham Airport, southwesterly winds gusted to 31 knots (35 mph) around midnight on the 8th/9th, and 32 knots (37 mph) was recorded, from a similar direction, late in the afternoon on the 15th. The 22nd and 23rd were both windy days. The southwesterly gusts peaked at 32 knots (37 mph) on the late morning of the 22nd, and 40 knots (46 mph) after dawn on the 23rd. No further gusts above 30 knots (34 mph) occurred during August

 

 

Fog

 

No fog was observed in this part of Shoreham during the month, although several days had mist, drizzle and hill fog, especially during the first half of August.

 

Statistics for August 2024

 

Reporting Site	Highest Temp	Lowest Temp	Rain Total (mm)	Wettest	Rain days
Shoreham A/P	26.9	8.0	47	16	8
Thorney Island	27.1	9.8	33	9	10
Gatwick A/P	31.5	7.7	39	9	11
Herstmonceux	29.0	9.6	70	13	15
Bournemouth (Hurn)	29.7	7.1	49	17	12
Middle Wallop	29.4	8.3	36	13	10
Dieppe	33.0	12.0	33	12	13

• Rainfall totals unreliable for all English stations

                                                            Very Mild and Wet

Temperatures

The average maximum temperature during December 2023 in Shoreham was 10.5 Celsius (51F), and that was around 1.5  Celsius (<3F) above normal for the time of year.  The  average minimum temperature was 6.7 Celsius (44F), and that  was also close to 1.5 Celsius (<3F) above the December average.  Overall, it was the 3rd mildest December in the area since 1880. Only the Decembers of 1934 and 2015 were milder.

The highest temperature recorded during the month was 14.1 Celsius (57F) on the 21st, but the maximum was 13.3 Celsius (56F) on the 9th, and a further 8 days had maxima above 12 Celsius (54F) including 6 out of the last 10 days of the month. The coolest weather occurred at the beginning of the month, with each of the first 7 days having highs below 10 Celsius (50F).  Only 3 other days had maxima below 10 Celsius (50F), and just 1 of these days had a maximum below 9 Celsius (48F). On the 13th, the top temperature was 8.7 Celsius (48F). During the first week of December there were 5 days with maxima below 9 Celsius (48F), but only 3 of these days had highs under 8 Celsius (46F). The 5th had a maximum of 6.5 Celsius (44F), with 3.7 Celsius (39F) and 0.1 Celsius (32F)  recorded on the 1st and 2nd respectively.   

There were several mild nights during December, and on 7 occasions the temperature remained above 10 Celsius (50F). All of the mild nights occurred after mid month. The highest minimum was 11.7 Celsius (53F) on the 25th, but 11.2 Celsius (52F) occurred on the 19th, and 10.9 Celsius (52F) on the 24th. A further 10 nights had minima ranging from 7 to 10 Celsius (45-50F). Only a few cold nights occurred in December. Although 9 nights had minima below 5 Celsius (41F), including 3 nights after mid month, only 5 nights had lows under 4 Celsius (39F). The last of these coldest nights was the 14th, when 2.9 Celsius (37F), the other low temperatures all occurred during the first week and included lows of minus 1.4 Celsius (30F) on the 1st and minus 2.9 Celsius (27F) on the 2nd.  

The sea temperature was briefly around 9 Celsius (48F) during the first week, otherwise it 10 or 11 Celsius (50-52F) throughout the month.

 

Frost

 

There were 3 air frosts during December, and that was 1 below average. The first 3 nights had air frost, although it was slight on the 2nd with a low of minus 0.9 Celsius (30F) recorded. The 6th had an air minimum of 0.0 Celsius (32F), but a grass frost occurred, 1 of  8 noted during the month.  That was 2 below the average.  There were grass frosts on 3 consecutive nights commencing on the 14th, but the lowest temperature was only minus 1.1 Celsius (30F) recorded on the 14th. All the other grass frosts occurred during the first 8 nights of December, the lowest temperatures were minus 3.3 Celsius (26F) on the 2nd, and minus 3.9 Celsius (25F) on both the 1st and 6th. 

 

Rain

 

Rainfall in December amounted to 148.4 millimetres (5.8 ins.),  which was around 30%  above the monthly average.  Measurable rain fell on 24 days, which was 4 days above the average, and  wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 16, which was  1 day above the average. The first day of the month was dry,  but precipitation  commenced on the evening of the 2nd and continued, almost without break, until the afternoon of the 5th. Daily rainfall totals included 3.6 millimetres (0.14 ins.) on the 2nd, 30.6 millimetres (1.2 ins.) on the 3rd and 7.6 millimetres (0.3 ins.) on the 4th. Further heavy rain at the end of the week resulted in 18.0 millimetres (0.71 ins.)  on the 7th and 21.0 millimetres (0.82 ins.)  There were no completely dry days during the following week, although the only day when more than 4 millimetres (0.16 ins.) of rain occurred was on the 10th, when 7.6 millimetres (0.3 ins.) were measured. The 16th and 17th were both dry days, and no measurable rain fell on 4 out of the following 6 days. However, on the 19th, heavy rain and drizzle produced a total of 13.0 millimetres (0.51 ins.). The last week of the month stayed unsettled and there was heavy rain at times. Daily totals included 8.2 millimetres (0.32 ins,),  7.8 millimetres (0.31 ins.) and 8.8 millimetres (0.35 ins.) on the 25th, 27th and 30th respectively.  Overall, it appears that 2023 was the 3rd wettest year in the area for at least 160 years with a total of 1218.8 millimetres (48 ins.). That was more than 30% above the long-term annual average.  The year included 6 months with totals exceeding 100 millimetres (4 ins. ) per month, including each of the last 3 months of the year, which yielded a combined total of 563.6 millimetres (22.2 ins.) of rain. 

 

Hail

Hail around 5-7 millimetres (0.3 ins) in diameter fell during a heavy shower just after midnight on the 31st.  

 

Thunder

Two thunderstorms  occurred either side of midnight on the 30th/31st. The centres of the storms appeared to be to the southwest and northwest of Shoreham and 5 thunderclaps were heard.

 

Snow

 

There was light snow, followed by moderate freezing sleet (but mostly rain) mid to late evening on the 2nd. The resulting slush remained on the grass until about 0400 hours on the following morning.

 

Wind

 

Apart from the occasional interlude of east to southeast winds ahead of Atlantic depressions, mainly at the beginning of December, the month was very much dominated by winds from between southwest and northwest. Winds were strong at times,  particularly at the beginning of the second week, and again after the 20th.  At Shoreham Airport,  south to southeasterly winds peaked at 32 knots (36 mph) in the early hours of the 4th,  and winds from  a similar direction reached 33 knots (38 mph) on the morning of the 9th, with southwesterly winds also gusting to 33 knots (38 mph) in the afternoon and evening. Southwesterlies gusted to 34 knots (39 mph) on the afternoon of the 10th and the early hours of the 11th. The 21st was the next windy day with west, then northwesterly, winds reaching 35 and 36  knots (40-41 mph) in the early morning and late afternoon  respectively.  The 24th was windy all day with the highest gust of 38 knots (43 mph) from the west-southwest occurring during the afternoon.  Southwesterly gusts of 33 knots (38 mph) occurred early in the evening on the 25th, with southwesterly winds again prominent on the 27th with gusts to 38 knots (43 mph) in the afternoon. The windy conditions continued throughout the 28th, with the top gust of 37 knots (42 mph) occurring during the morning. After a brief lull, west-southwesterly gusts reached 35 knots (40 mph) on the afternoon  of the 29th. South to southwesterly winds strengthened on the evening of the 30th, with 37 knots (42 mph)  recorded either side of midnight. The 31st was the windiest day of the month with the highest gust of 41 knots (49 mph) occurring in the early hours.

 

 

Fog

 

Although there was sunshine at times, areas of freezing fog were close by through much of that day, with the densest fog occurring close to the river.

 

Statistics for December 2023

 

Reporting Site	Highest Temp	Lowest Temp	Rain Total (mm)	Wettest	Rain days
Shoreham A/P	13.9	-3.5	139	29	19
Thorney Island	13.9	-2.3	169	33	20
Gatwick A/P	14.1	-3.8	180	40	20
Herstmonceux	14.0	-4.2	142	39	23
Bournemouth (Hurn)	14.2	-4.1	212	43	20
Middle Wallop	14.2	-4.1	196	40	20
Dieppe	13.7	-2.7	59	13	19

• Rainfall totals unreliable for all stations

Very Dry and Anticyclonic

Temperatures

The average maximum temperature during February 2023 in Shoreham was 10.0 Celsius (50F), and that was almost 1 Celsius (<2F) above normal for the time of year. The average minimum temperature was 3.8 Celsius (39F), and that was around 0.1 Celsius (<0.2F) below average for February.

The highest temperature recorded during the month was 13.8 Celsius (57F) on the 19th, but this was the only maximum above 13 Celsius (55F). The next mildest day was the 3rd with 12.1 Celsius (54F) recorded. However, a further 11 days had maxima above 10 Celsius (50F), including the spell between the 13th and 19th which culminated in the mildest day of the month. There were no cold days during February, although the temperature failed to reach 9 Celsius (48F) on 7 occasions, including the last 3 days of the month. However, only 3 of these less mild days had maxima below 8 Celsius (46F). On the 26th and 28th there were highs of 7.9 Celsius (46F) and 7.8 Celsius (46F) respectively, but the coolest day of the month was the 7th with a maximum of 7.2 Celsius (45F).

There were no particularly mild nights during February, but a minimum of 9.3 Celsius (49F) occurred on the 18th,  and 2 other nights had minima above 8 Celsius (46F). The 3rd had a low of 8.4 Celsius (47F), and  the 17th had a minimum of 8.8 Celsius (48F). A further 9 days had minima above 5 Celsius (41F), including each night between the 16th and 23rd.  The coldest nights were mainly confined to the second week and the last 5 nights of the month. There were 12 nights with minimum temperatures below 3 Celsius (37F), with all of these colder nights  occurring between the 6th and 14th, and after the 23rd. The coldest nights occurred in the earlier period with minima of minus 1.6 Celsius (29F) and minus 3.7 Celsius (25F). 

The sea temperature was around 7 or 8 Celsius (45-46F), but briefly reached 9 Celsius (48F) after mid-month.

 

Frost

 

There was air frost on 4 nights during February,   around 1 night below average. Air frost occurred on 3 consecutive nights, beginning on the 7th, although the frost on the last night was slight with a minimum termperature of minus 0.6 Celsius (31F). The other air frost occurred on the 14th with a low of minus 0.8 Celsius (30F)  recorded. Grass frost occurred on 17 nights,  which was 3 nights above average. Grass frost occurred on the first night of the month, and after 3 frost-free nights, there was frost on every night until the 15th, except for the 12th. The 19th was the only night with a grass frost between the 16th and 23rd, but the last 5 nights of the month were frosty.  Grass temperatures were between minus 1 Celsius (30F) and minus 4 Celsius (25F) on most nights, but the 14th had a low of minus 5.6 Celsius (22F) and the grass temperature fell to minus 6.1 Celsius (21F) on the 8th. 

 

Rain

 

Rainfall in February amounted to 7.2 millimetres (0.28 ins.), which was only around 12% of the monthly average. It was the driest February this century.  Measurable rain fell on 10 days, which was 6 days below the average, although, interestingly, 4 of the 10 ‘rain’ days had no rain falling, ,  but dew or melted frost contributed to the monthly total.  Wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 3, which was 9 days below the average.  There was no measurable rain during the first 14 days of February, but 1 millimetre (0.04 ins.) of dew and frost were collected on 4  different nights. Rain and drizzle occasionally fell between the 16th and 18th, but the total for the 3 days was only 1.8  millimetres (0.07 ins.). Light rain fell at times on both the 21st and 22nd, and the 22nd was the wettest day of the month, but with a mere 2.6 millimetres (0.1 ins.) measured. The last measurable rain of the month fell on the evening of the 28th, but only another 1.4 millimetres (0.05 ins.) were added to the monthly total.  

 

Hail

No hail was observed in this part of Shoreham.  

 

Thunder

No thunder was heard in this part of Shoreham.

 

Snow

 

There was no sleet or snow observed in this part of Shoreham.

 

Wind

 

High pressure dominated during February with the average daily reading of 1030 millibars being around  13 millibars above average. The centres of the high pressure areas were over the country,  or west or southwest of the British Isles, although the last few days of the month saw a migration of the anticyclones northwestwards. The wind was light or gentle during the first half of February,  but southwesterlies during the third week, and northerlies during the fourth week, were quite brisk at times.  At Shoreham Airport, the highest gust recorded during the month was 28 knots (32 mph) from the southwest on the morning of the 17th.       

 

Fog

 

There was  fog observed on 3 mornings during February. On the 7th there was dense freezing fog until late morning towards the west, with similar fog distribution occurring on the 14th, and there was another misty Tuesday on the 21st, with hill fog lowering at times until early afternoon.

 

Statistics for February 2023

 

Reporting Site	Highest Temp	Lowest Temp	Rain Total (mm)	Wettest	Rain days
Shoreham A/P	13.6	-4.6	7	2	9
Thorney Island	13.4	-4.0	12	9	7
Gatwick A/P	14.1	-6.7	8	4	5
Herstmonceux	13.1	-2.4	11	3	11
Bournemouth (Hurn)	13.7	-7.3	21*	10	9
Middle Wallop	13.7	-5.8	14*	8	8
Dieppe	15.2	-3.9	7	3	8

* Totals unreliable

 

 

Cold, becoming Very Mild

Temperatures

The average maximum temperature during December 2022 in Shoreham was 7.5 Celsius (45F), and that was almost 2 Celsius (3.5F) below normal for the time of year. The average minimum temperature was 3.2 Celsius (38F), and that was more than 2 Celsius (3.5F) below average for December. Overall, it was the coldest December in the area for 12 years.

The highest temperature recorded during the month was 13.2 Celsius (56F) on the 13th, but the temperature reached 12.3 Celsius (54F) on the 19th, and there were 10 other days with maxima above 10 Celsius (50F), including 6 days when the temperature was 11 Celsius (52F) or higher.. All of these very mild days occurred after the 18th. After a relatively mild start to the month, with 5 out of the first 6 days having maxima above 7 Celsius (45F), it became much colder. Between the 11th and 16th, day-time temperatures remained below 3 Celsius (37F), although only 2 of these cold days had maxima below 2 Celsius (36F). On the 11th, a high of 0.9 Celsius (34F) occurred, with 1.8 Celsius (35F) recorded on the 15th.

There were several mild nights during December, all of them occurring after the 18th. On 2 nights the temperature stayed above 10 Celsius (50F) . On both the 25th and 31st lows of 10.3 Celsius (50F) were measured, and a further 5 nights had minima above 8 Celsius (46F). The first week of December had minimum temperatures between 2 and 5 Celsius (36-41F), but it then turned much colder. On the 10th and 17th minima of minus 4.3 Celsius (24F) occurred, but the coldest night of the month was the 11th with a low of minus 5.2 Celsius (23F). 

The sea temperature decreased from 12 Celsius (54F) at the beginning of the month to around 9 Celsius (48F) at the start of the second week. It then changed little during the remainder of the month.

 

Frost

 

There was air frost on 10 nights during December,  around 7 nights above average. All of the air frosts occurred between the 8th and 17th. Most of the frosts were moderate with minima between minus 2 and minus 5 Celsius (28-23F), but 4 nights only had a slight frost, and on 2 of those nights, the 12th and 13th, minimum temperatures were above minus 1 Celsius (30F). Grass frost occurred on 12 nights, that was only 2 nights above average. The grass frosts coincided with the air frosts, except for 1 night, the 12th, when a grass low of 0.0 Celsius (32F) occurred. The 18th, 21st and 27th each had grass frost but no air frost. The lowest grass temperature was minus 8.3 Celsius (17F) on the 17th, but lows between minus 5 and minus 6 Celsius (23-21F) occurred on the 9th, 10th, 11th and 18th. 

 

Rain

 

Rainfall in December amounted to 119.0 millimetres (4.7 ins.), which was only slightly above the monthly average.  Measurable rain fell on 16 days, which was 4 days below the average, and wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 12, which was also 4 days below the average.  Apart from showers on the 2nd, which gave 0.8 millimetres (0.03 ins.), the only measurable precipitation during the first 10 days was on the 10th, when 0.4 millimetres (0.02 ins.) of dew were measured. On the afternoon of the 11th there was moderate rain, and it fell with a temperature of minus 2 Celsius (28F). Although only 4 millimetres (0.16 ins. ) of rain were measured, the ice that formed on untreated surfaces was both hazardous and damaging. The ice remained on shaded areas of local pavements and roads until late on the 17th. On the 18th, it rained all day giving a total of 33.2 millimetres (1.3 ins.) and 6.8 millimetres (0.27 ins.) of rain fell on the following day. In fact, there were no completely dry days during the rest of the month, with daily totals including 6.6 millimetres (0.26 ins.) on the 22nd, 10.2 millimetres (0.40 ins.) on the 27th, 13.6 millimetres (0.53 ins.) on the 30th, and 19.8 millimetres (0.8 ins.) on the last day of the year.  

 

Hail

No hail was observed in this part of Shoreham.

 

Thunder

No thunder was heard in this part of Shoreham.

 

Snow

 

A few snowflakes were observed in the freezing rain on the afterrnoon of the 11th, and light snow fell for less than hour in the evening. A very thin layer covered the ground until late afternoon on the following day. Thereafter, a few well-scattered patches remained in shaded spots until late on the 17th. Over, and to the north of, the South Downs,  there were 3 to 5 centimetres (1-2 ins.) of snow, and the ground stayed snow-covered for 6 days.

 

Wind

 

In the first half of December, winds were mainly light or moderate and blowing from the north or northwest. After the 17th, the winds were  persistently from between south and west and generally fresh or strong. At Shoreham Airport, the first gust of the month above 30 knots (34 mph) occurred at midnight on the 19th when south-southwesterlies reached 33 knots (38 mph). The rest of the day was breezy with 38 knots (43 mph) occurring at midday. On the 27th, southwesterly gusts reached 35 knots (40 mph) late in the evening, and on the following afternoon a gust of 40 knots (46 mph) was recorded, also from the southwest. The strong wind continued into the morning of the 29th with 42 knots (48 mph) recorded before dawn. On the morning of the 30th there were strong south-southeasterly winds, these peaking at 41 knots (47 mph). Southwesterly winds returned on the last day of the month, and several gusts reached 32 or 33 knots (37-38 mph).       

 

Fog

 

Mist thickened into fog at times on the morning of the 1st.

 

Statistics for December 2022

 

Reporting Site	Highest Temp	Lowest Temp	Rain Total (mm)	Wettest	Rain days
Shoreham A/P	13.1	-6.3	*	27	22
Thorney Island	13.5	-3.1	*	*	*
Gatwick A/P	13.5	-8.4	*	35	17
Herstmonceux	14.3	-4.9	*	40	24
Bournemouth (Hurn)	14.0	-8.6	*	28	18
Middle Wallop	13.4	-6.7	*	36	19
Dieppe	16.8	-5.4	86	27	21

* Totals unreliable