Extremely Wet and Very Mild
Temperatures
The average maximum temperature during October 2023 in Shoreham was 17.9 Celsius (64F), and that was nearly 2 degrees Celsius (3.5F) above normal for the time of year. Only the Octobers of 1948 and 2022 had higher average maxima in local records dating back to 1880. The average minimum temperature was 11.4 Celsius (53F), which was over 1 degree Celsius (2F) above the October average. Only 6 Octobers have had milder nights during the last 143 years.
The highest temperature recorded during the month was 23.0 Celsius (73F) on the 1st, but 22.8 Celsius (73F) occurred on the 8th, with 22.4 Celsius (72F) on the following day. A further 5 days had maxima above 20 Celsius (68F), with the last of these pleasantly warm days occurring on the 19th. Some cooler days occurred, but just 11 days had maxima below 17 Celsius (63F), with all of the cooler days after the 13th. Only 4 days had maxima below 15 Celsius (59F). The 16th, 27th and 29th had highs of 14.2 , 14.9 and 14.1 Celsius (58, 59 and 57F) respectively, but the coolest day of the month was the 15th with a high of 12.6 Celsius (55F).
There were no record-breaking warm nights during October, but the temperature only fell to 17.4 Celsius (63F) on the 1st, and 3 consecutive nights, beginning on the 11th, had minima between 16.0 and 16.6 Celsius (61-62F). On many nights (12) the minimum temperature ranged from 10 to 13 Celsius (50-55F), but cooler nights occurred, more especially around the middle of the month. On 9 occasions the temperature fell below 10 Celsius (50F), but only 3 nights had lows under 7 Celsius (45F). The temperature dipped to 6.7 Celsius (44F) on the 22nd, with 5.1 Celsius (41F) measured on the 15th, but the coldest night of the month was the 15th with a low of 2.6 Celsius (37F).
The sea temperature was around 18 or 19 Celsius (64-66F) during the first fortnight but slowly decreased to 16 Celsius (61F) by the end of the month.
Frost
There were no air or grass frosts during October. The lowest grass temperature was 0.6 Celsius (33F) on the 15th.
Rain
Rainfall in October amounted to 241.4 millimetres (9.5 ins.), which was well over double the monthly average. It was the second wettest October (behind October 2000) since local records began in 1880. Measurable rain fell on 18 days, which was 1 day below the average, and wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 16, which was 3 days above the average. No measurable rain fell during the first 10 days of the month, although dew on both the 8th and 9th amounted to 0.6 millimetres (0.02 ins.) and was added to the monthly total. The first significant rain of the month commenced on the evening of the 11th and by the following morning 10.2 millimetres (0.4 ins.) had fallen. Further rain fell on the following evening and added another 17.2 millimetres (0.7 ins.) to the total by the morning of the 13th. Some of the rain was heavy during the 13th, and another 6 millimetres (0.25 ins.) fell after 0900 GMT, the end of the rainfall day. After 4 dry days, heavy rainfall began in earnest, with 29.8 millimetres (1.2 ins.) falling on the 18th, another 20.2 millimetres (0.8 ins.) fell on the 19th, with 11.8 millimetres (0.45 ins.) on the 20th. The 22nd was dry, but the last 8 days of the month produced a total of 137.8 millimetres (5.4 ins.) of rain. This was made up of the following daily falls: 17.4 millimetres (0.7 ins.) on the 24th, 10.8 millimetres (0.4 ins.) on the 26th, 46 millimetres (1.8 ins.) on the 27th, 23.8 millimetres (0.95 ins.) on the 28th, 11 millimetres (0.4 ins.) on the 29th, and 16.8 millimetres (0.7 ins.) on the last day of the month.
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
Although the first half of October was mostly anticyclonic with winds lighter than average for a mid-autumn month, the second half of October was decidedly cyclonic, resulting in the average pressure for the month some 7mb below the average. The net effect was to have southwesterly winds dominant, accounting for around half of the daily readings, but with a mixture of winds after mid month as fronts, and occasionally depressions, tracked across southern Britain. Overall, it was less windy than an average October. At Shoreham Airport, the first gusts above 30 knots (34 mph) did not occur until the morning of the 13th, when southwesterly winds increased and peaked at 39 knots (44 mph) in the late morning. Increasing east to southeasterly winds on the afternoon of the 18th gusted to 35 knots (40 mph) in the early evening, before veering southwesterly and gusting to 41 knots (47 mph) in the late evening. Southwesterly gusts of 33 knots (38 mph) occurred on the morning of the 21st, and there then followed a windy end to the month. On the 28th, south to southwesterly gusts peaked at 35 knots (40 mph) in the late evening, followed by southwesterly gusts up to 39 knots (44 mph) on the following morning. A gust of 33 knots (38 mph) in the early hours of the 30th was the last significant gust of the month.
Fog
There was early fog at the airport on the morning of the 10th, and mist enveloped the hills on the morning of the 11th.
Statistics for October 2023
| Reporting Site | Highest Temp | Lowest Temp | Rain Total (mm) | Wettest | Rain days |
| Shoreham A/P | 22.0 | 2.3 | * | * | 15 |
| Thorney Island | 22.5 | 3.3 | 20 | ||
| Gatwick A/P | 25.3 | -1.4 | 17 | ||
| Herstmonceux | 23.5 | 2.4 | 15 | ||
| Bournemouth (Hurn) | 23.1 | 0.0 | 18 | ||
| Middle Wallop | 23.6 | -0.3 | 19 | ||
| Dieppe | 27.5 | 2.0 | 91 | 19 | 19 |
- Rainfall totals unreliable for all stations