FLAMING JUNE: HOTTEST JUNE ON RECORD AT ARMAGH, DRIEST FOR 8 YEARS AND
SUNNIEST FOR 14 YEARS
Armagh Observatory reports that June 2023 was the warmest June at Armagh for at least 228 years. The month was also much sunnier and much drier than average.
The mean temperature, that is, the average of the daily maximum and minimum temperatures, was approximately 17.35 degrees Celsius (63.2 Fahrenheit). This was a record 3.92 C warmer than the 225-year long-term (1796-2020) average June temperature at Armagh (13.43 C) and 3.30 C warmer than the most recent (1991-2020) 30-year June average (14.05 C). Following a relatively cool June 2022, this was the warmest June on record at Armagh, beating the previous record set nearly 180 years ago (16.9 C in June 1846) by nearly 0.5 C.
The six warmest Junes at Armagh are now June 2023 (17.4 C), June 1846 (16.9 C), June 1826 (16.4 C), June 2018 (16.2 C), June 1887 (15.9 C), and June 1970 (15.8 C).
Although the month was much warmer than average there were no exceptionally hot days. The highest maximum air temperature was a warm 28.5 C on the 13th, but this was only the ninth-warmest June day on record at Armagh. This was followed by 26.9 C on the 16th and 26.6 C on the 15th. Rather, the month’s exceptional average temperature occurred because each day’s maximum air temperature was warmer than the most recent (1991-2020) 30-year average of 18.3 C. The three coolest days (lowest maximum temperature) were 18.5 C on the 7th, 18.6 C on the 8th, and 18.7 C on the 30th, and the mean monthly maximum temperature of 22.7 C exceeded the most recent 30-year average (18.3 C) by a remarkable 4.4 C.
The nights too were relatively warm, the warmest occurring on the 24th with a highest minimum temperature of 17.2 C. This was followed by 16.1 C on the 11th and then by 15.5 C, a value that occurred on three nights: the evening of the 17th, and early morning on the 23rd and 25th.
The 24th was the warmest June night on record at Armagh, in a daily series of maximum and minimum temperatures that began 180 years ago in 1843. Before being overtaken by the 24th the 11th, with a minimum temperature of 16.1 C, had been the warmest June night for 18 years and for a brief period the eighth-warmest June night on record.
The coolest night or lowest minimum temperature was 7.4 C on the 7th followed by 7.9 C on the 22nd and 8.0 C on the 8th. The average minimum temperature this month (12.0 C) was 2.1 C warmer than the most recent (1991-2020) 30-year average (9.9 C).
There were three nights with ground frost, that is, nights with minimum grass temperatures less than or equal to zero Celsius. These were -0.8 C on the 3rd, -0.5 C on the 7th, and 0.0 C on the 8th. There were no night-time air frosts.
Four buzzards were seen circling overhead on the morning of the 11th. The same evening a very large flock of possibly more than 150 crows was seen flying towards the south-west. A clattering of more than 200 jackdaws was also seen flying south-west on the evening of the 22nd.
Total precipitation was 42.0 mm (1.65 inches), with no trace values. This was approximately 66% of the 183-year long-term (1838-2020) June precipitation at Armagh (63.7 mm) and 67% of the most recent (1991-2020) 30-year June average (62.9 mm). June 2023 was the driest June at Armagh for eight years, that is, since 29.45 mm of precipitation including three trace values was recorded in June 2015. The wettest day was the 16th with 9.4 mm of rainfall, followed by the 23rd with 7.2 mm and the 26th with 5.6 mm.
Although the month was much drier than average, still there was measurable precipitation on more than half (16) of the 30 days of the month. Thunder was heard on the 18th, 19th, 20th, and 25th.
June 2023 was much sunnier than average with a total of 220.1 hours of strong sunshine. This was the sunniest June at Armagh for 14 years, that is, since June 2009 (223.3 hours of strong sunshine). The month had nearly 38% more strong sunshine than the 140-year long-term (1881-2020) average at Armagh (159.7 hours) and 52% more than the most recent (1991-2020) 30-year average (144.6 hours). The sunniest day, with 13.2 hours of strong sunshine, occurred on both the 4th and 22nd, followed by the 9th with 13.1 hours.
These data refer to observations at Armagh Observatory, which has been recording the weather at Armagh since 1795.
For further information, please contact:
Professor Mark E. Bailey
Emeritus Director of Armagh Observatory
Armagh Observatory and Planetarium