April 2021 was cooler than average (6.32°C versus an average of 8.69), drier than average (7.00 mm versus an average total of 34.78) and calmer than average (a wind run of 1964 miles versus an average of 2792).
The month was cold and dry with a number of records broken. At 05:24 on the 7th, the minimum temperature fell to -4.4°C, the lowest temperature ever recorded here in April. This beat the previous April low of -1.9°C set in 2013 and 2017. The maximum temperature in the month was 17.7°C, recorded at 15:00 on the 20th. The monthly avaerage was 6.3°C, the lowest average April temperature ever here. The average daily high temperature was 11.7°C (1.3°C below the mean) and the average daily low temperature was 0.9°C (4.5°C below the mean). This was easily the lowest for April, which was previously 2.8°C set in 2016.
The warmest day was the 20th with an average temperature of 11.2°C, and the coldest day was the 6th with an average temperature of 0.8°C. There were 11 frost days in the month, a record for April. The average wind chill was 5.8°C, and the average dew point was 1.0°C. The sunniest day was the 24th with 10.31 hours and there were 229.74 sunshine hours in the month, a record for April.
Rainfall in the month was 7.0 millimetres recorded on 9 days. The yearly total was 187.8 millimetres, 113% of the average for the end of April. The wettest day was the 27th with 2.4 millimetres. The highest rain rate of 3.0 millimetres per hour was recorded at 23:25 on the 27th. There was 2.5 millimetres of snow recorded in the month.
The highest barometric pressure of 1034.4 millibars was at 10:05 on the 15th. The lowest pressure was 1006.7 millibars at 19:08 on the 27th. The average pressure in the month was 1022.41 millibars, an April high. The highest humidity was 96% and the monthly average humidity was 71%. The lowest humidity was 28% at 13:02 on the 22nd.
Wind speeds were lower than average, with the highest wind gust speed of 28 mph being recorded at 14:19 on the 8th. The maximum wind speed was 16 mph at 14:21 on the 8th. The wind run was 1963.5 miles, a low for the month. The average gust speed in the month was 4.3 mph, and the average wind speed was 2.78 mph. The predominant direction was south easterly (132°).
The maximum high solar radiation recorded at 13:25 on the 3rd was 1079 w/m², the highest of 2021 so far.. The average solar radiation for the month was 166 w/m². The highest U.V. Index was 4.0 recorded at 13:03 on the 25th, the highest since September 8th 2020, when 4.4 was recorded.