FEBRUARY WARMER, DRIER AND DULLER THAN AVERAGE. WINTER 2024/2025 WARMER AND DRIER THAN AVERAGE, WITH ABOUT AVERAGE SUNSHINE
Armagh Observatory reports that February 2025 at Armagh was warmer, drier, and duller than average. In a month largely dominated by higher-than-average atmospheric pressure there were no gales or named storms. The meteorological winter 2024/2025, that is, the three months December 2024, and January and February 2025, was warmer and drier than average with about average sunshine.
The mean temperature this February was approximately 6.5 degrees Celsius (43.6 Fahrenheit). This was 1.81 C warmer than the 225-year (1796-2020) long-term February average at Armagh (4.65 C) and 1.13 C warmer than the most recent (1991-2020) 30-year average (5.33 C). This extends to seven years a trend in which each February at Armagh since 2019 has been warmer than average. Still, February 2025 was the coolest February at Armagh for four years, that is, since February 2021 (average temperature 6.04 C).
Recent 30-year average February temperatures show the same general trend. Over the last thirty years the 30-year average February temperatures have increased at a rate of approximately 0.36 C per decade. People with lawns are now having to consider cutting their grass around the end of February instead of early to mid-March.
The highest maximum air temperature, usually the warmest day, was 13.9 C on the afternoon of the 23rd, followed by 13.5 C on the 20th, and 13.3 C attributed to the 19th. The 23rd was the warmest February day at Armagh since a run of several much warmer days occurred during the interval 21st to 27th February 2019. The 6-day period from the 19th to the 24th of February 2025 was very mild for February, with an average daily maximum of 13.1 C, much warmer than the most recent (1991-2020) 30-year average maximum for February at Armagh (8.6 C). Similarly, the average daily minimum for the same six days was 6.8 C compared with the most recent (1991-2020) 30-year average February minimum of 2.0 C.
The lowest maximum air temperature, usually the coldest day, was 4.7 C on the 13th, followed by 5.4 C on both the 10th and 11th.
The highest minimum temperature, usually the warmest night, was 9.0 C. This was attributed to the 21st, although the actual minimum occurred on the afternoon of the 20th. This was followed by 8.0 C on the 4th, and then by 6.9 C attributed to the 2nd, 20th, and 23rd.
The three lowest minimum air temperatures, or coldest nights, this month were -1.6 C on the 6th, followed by -1.2 C shortly after the time of observations on the 6th but attributed to the 7th, and then by 0.5 C on the 27th.
This month there were 12 nights with ground frost, that is, nights with minimum grass temperatures less than or equal to zero Celsius. The three lowest of these were -7.2 C on the 7th, -6.9 C on the 6th, and -5.3 C on the 28th. There were nominally two nights with air frost, the 6th and 7th, but both occurred around the time of observations on the 6th.
There was no sleet or snow this February, but a rainbow was observed late afternoon on the 23rd. Unlike January, this month was relatively calm and dominated by high pressure. There were no named storms, although there were strong winds approaching gale force on the morning of the 23rd. The mean atmospheric pressure, reduced to mean sea level and observed at approximately 09:00 GMT each day, was approximately 1017.7 mbar. This was 4.4 mbar higher than the most recent (1991-2020) 30-year average February pressure at Armagh, namely 1013.4 mbar.
The highest atmospheric pressure this month was approximately 1044 mbar on the 6th. This was the fifth highest February pressure at Armagh in a calibrated series starting in 1850 and the highest February atmospheric pressure at Armagh for two years, that is, since nearly 1047 mbar was recorded by the Automatic Weather Station on the morning of 5th February 2023.
Rooks and gulls were observed mobbing a buzzard around the time of observations on the 3rd and 18th.
Total precipitation this February was a drier-than-average 42.1 mm including two trace values, that is, 42.0 mm if trace values are ignored. This is approximately 76% of the 183-year long-term (1838-2020) average February precipitation at Armagh (55.49 mm) and 71% of the most recent (1991-2020) 30-year average (59.02 mm). The wettest days were 7.2 mm on the 21st, 7.0 mm on the 3rd, and 5.9 mm on the 20th.
With 56.0 hours of strong sunshine at Armagh, February 2025 was duller than average with approximately 86% of the 140-year (1881-2020) long-term average (65.4 hours) and 79% of the most recent (1991-2020) 30-year average (70.9 hours).
Although February 2025 was not exceptionally dull, the month included an unusually long series of ‘dull’ days, defined as days with less than 0.5 hours of strong sunshine. In this case, there were 11 consecutive dull days, from the 8th to 18th, which together produced a total of less than 25 minutes of strong sunshine including six consecutive days from the 13th to the 18th with no strong sunshine at all. This six-day period was the first continuous sequence of six sunless February days at Armagh for 59 years, that is, since the 7th to the 12th of February 1966. The sunniest day this month was the 28th with 7.6 hours of strong sunshine, followed by the 6th with 7.2 hours, and the 5th with 6.9 hours.
Taking the three months December 2024 and January and February 2025 together, the meteorological winter 2024/2025 was warmer and drier than average at Armagh and with about average sunshine.
The mean winter temperature was 6.02 C, approximately 1.54 C warmer than the 225-year (1796/1797-2020/2021) long-term winter average at Armagh (4.48 C) and 0.81 C warmer than the most recent (1991/1992-2020/2021) 30-year average (5.21 C).
As with February, recent winters at Armagh have become a lot warmer than those many years ago. Over the last 30 years the 30-year average winter temperatures at Armagh have increased at a rate of approximately 0.29 C per decade.
With a total of 129.6 mm of precipitation including 18 trace values, winter 2024/2025 was much drier than average at Armagh. This is approximately 63% of the 183-year (1838/1839-2020/2021) long-term average at Armagh (207.0 mm) and 60% of the most recent (1991/1992-2020/2021) 30-year average (215.7 mm). This was the driest winter at Armagh for eight years, that is, since winter 2016/2017 (total precipitation 127.35 mm including 15 trace values), and the twelfth driest winter at Armagh since records of daily rainfall began in 1838.
Total winter sunshine was 154.2 hours, approximately 3% more than the 140-year long-term (1881/1882-2020/2021) winter average at Armagh (149.7 hours) and nearly 5% less than the most recent (1991/1992-2020/2021) 30-year winter average (161.5 hours). Although this winter had about average sunshine, it was the dullest at Armagh for three years, that is, since winter 2021/2022 (145.6 hours of strong sunshine).
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
College Hill
Armagh
BT61 9DG
Tel: 028-3752-2928
E-mail: mark.bailey@armagh.ac.uk
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