Rather Cool and Extremely Wet
Temperatures
The average maximum temperature during April 2023 in Shoreham was 13.9 Celsius (57F), and that was around 1 Celsius (<2F) below normal for the time of year. The average minimum temperature was 6.2 Celsius (43F), which was close to average for April.
The highest temperature recorded during the month was 17.8 Celsius (64F) on the 19th, but only 4 other days, the 15th, 20th, 28th and 30th, had maxima above 16 Celsius (61F). The mildest of these days was the 28th, with a high of 16.8 Celsius (62F). On most days (21) the maximum temperature was in the range 12 to 16 Celsius (54-61F), but there were 4 cooler days, the 4th, 9th and 12th had maxima between 11 and 12 Celsius (52-54F), but the temperature on the 14th only reached 9.4 celsius (49F).
There were no especially mild nights during April, although a minimum of 11.2 Celsius (52F) occurred on the 28th, and 4 nights, the 1st, 10th, 17th and 23rd, each had minima between 9 and 10 Celsius (48-50F). A further 5 nights had minima between 7 and 9 Celsius (45-48F). On many nights (15) the minimum temperature was in the range 4 to 7 Celsius (39-45F), but there were several colder nights. On 5 occasions the temperature fell below 4 Celsius (39F). The 25th, with a low of 2.6 Celsius (37F), was the only colder night after the 8th, but 3 nights during the first week of April had minima below 2 Celsius (36F). They were the 3 consecutive nights beginning on the 3rd. The only one of these nights to have a minimum temperature below 1 Celsius (34F) was the 5th, when 0.7 Celsius (33F) was recorded.
The sea temperature was around 9 Celsius (48F) at first, slowly rising to 12 Celsius (54F) by the end of the month.
Frost
There were no air frosts during April. Grass frost occurred on 5 nights , which was 2 nights below the average. The only grass frost after the 8th was on the 25th, when minus 0.6 Celsius (31F) was recorded. A similar minimum occurred on the 8th, with the other 3 grass frosts occurring between the 3rd and 5th. The lowest temperature on these nights was minus 2.8 Celsius (27F), recorded on both the 4th and 5th.
Rain
Rainfall in April amounted to 111.6 millimetres (4.4 ins.), which was around 4 times the monthly average. It was the wettest April since 2012, but in records going back to 1880, April 2023 is ranked as the second wettest. So far this year there have been 3 months with rainfall exceeding 100 millimetres (4 ins.). Measurable rain fell on 15 days, which was 8 days above the average, and wet days (when 1 millimetre (0.04 ins.), or more, of rain falls) numbered 10, which was 5 days above the average. Only 7.2 millimetres (0.3 ins.) of rain fell during the first 8 days of April, with 6.8 millimetres (0.27 ins.) of that falling on the night of the 5th/6th. Very wet weather followed, this commencing overnight on the 9th. Over 53 millimetres (2.1 ins.) fell during the following 6 days, including 11 millimetres (0.4 ins.) on the 9th, and 18 millimetres (0.75 ins.) on both the 11th and 14th. Only 1 millimetre (0.04 ins.) of rain fell between the 15th and 21st, but in a fairly changeable end to the month 25 millimetres (1 in.) of rain fell on the 22nd and another 20 millimetres (0.8 ins.) were recorded on the 27th.
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
Pressure during April was very close to average overall, but day to day pressure changes were quite marked and, unusually, southwesterly winds were in the minority. There were 14 days when the wind blew from the northeasterly quadrant, but there were only 2 days with southwesterlies blowing. The wind direction during the rest of the month was equally divided between the other two quadrants (SE and NW). Winds were mostly gentle or moderate, but occasionally fresh or strong during the second and third weeks. At Shoreham Airport, there was a southwesterly gust of 33knots (39 mph) during the afternoon of the 10th, with 38 knots (43 mph), again from the southwest, occurring in the evening of the 11th. The strong wind continued throughout the 12th with southwesterly gusts in the afternoon peaking at 50 knots (57 mph) in the afternoon before veering westerly during the evening. During the rest of the month the wind mainly blew from a northeasterly quadrant, and although breezy at times, there were no further gusts above 30 knots (34 mph).
Fog
No fog was observed during the month in this part of Shoreham.
Statistics for April 2023
| Reporting Site | Highest Temp | Lowest Temp | Rain Total (mm) | Wettest | Rain days |
| Shoreham A/P | 17.2 | -0.6 | * | 25 | 16 |
| Thorney Island | 18.9 | -0.3 | * | 25 | 16 |
| Gatwick A/P | 18.8 | -3.4 | * | 40 | 19 |
| Herstmonceux | 17.2 | 0.0 | * | 20 | 15 |
| Bournemouth (Hurn) | 18.1 | -2.9 | * | 40 | 14 |
| Middle Wallop | 18.6 | -1.1 | * | 34 | 15 |
| Dieppe | 18.2 | -0.5 | 71 | 18 | 15 |
* Totals unreliable