December 2024 Climate Spherical-Up – Astronotes

DECEMBER 2024 DRIER AND MUCH WARMER AND DULLER THAN AVERAGE.  CALENDAR YEAR 2O24 MUCH WARMER AND DRIER THAN AVERAGE, AND SLIGHTLY DULLER.

Armagh Observatory stories that December 2024 was drier and far hotter and duller than common.  The typical December temperature was 7.0 C (44.7 F), roughly 2.4 C hotter than the 225-year (1796-2020) long-term December common at Armagh (4.64 C) and 1.8 C hotter than the newest (1991-2020) 30-year common (5.23 C).  

Calendar yr 2024, with a median temperature of 10.52 levels Celsius (50.9 Fahrenheit), was a lot hotter than common, and far drier and barely duller than common.  Other than January and the 4 months June to September, each month was hotter and a few a lot hotter than the corresponding most up-to-date (1991-2020) 30-year averages, resulting in 2024 being a lot hotter than common.  This was the fourth warmest calendar yr on document at Armagh in a 231-year-long every day temperature sequence starting in December 1794.  The six warmest years at Armagh are actually 2023 (11.1 C), 2022 (10.8 C), 2007 (10.6 C), and 2024, 2021 and 2006 (all roughly 10.5 C).  

This December the very best most air temperature, often the warmest day, was a really gentle 14.2 C occurring late night on the seventeenth.  This was adopted by 12.7 C and 12.6 C on the afternoon of the first and twenty fourth respectively.  Christmas Day was a gentle 12.0 C, the warmest Christmas Day at Armagh for eight years, that’s, because the twenty fifth of December 2016 (13.3 C).  New 12 months’s Eve (thirty first December 2024) was additionally comparatively gentle, with a most temperature of 11.8 C.  The flip of the yr noticed a change to a lot colder circumstances with a most temperature of seven.1 C on the first of January, 3.5 C on the 2nd, and far decrease temperatures later that week and into the second week of January.  

The bottom most air temperature this December, often the good day, was 3.6 C on the afternoon of the tenth, adopted by 4.5 C and 5.5 C on the eleventh and thirteenth respectively.  The 4 days from the tenth to the thirteenth, with a median most temperature of simply 4.8 C, was the good interval in what in any other case was a really gentle month with a median most temperature of 9.6 C. 

These chilly days had been related to excessive atmospheric stress, which on the time of observations (09:00 GMT) on the ninth reached 1043.5 mbar diminished to imply sea stage.  This was the sixth highest 09:00 GMT December atmospheric stress at Armagh and the very best December stress for 19 years, that’s, since 1044.4 mbar on twelfth December 2005.

The 2 highest minimal air temperatures, often the warmest nights, had been 10.4 C on the first and 10.2 C on the twenty fifth.  These gentle nights had been adopted by a minimal air temperature of 9.8 C on the night of the thirtieth, although attributed following regular meteorological conventions to the thirty first.

The bottom minimal air temperature, often the coldest evening, was -2.9 C on the early morning of the tenth.  This was adopted by -2.4 C on the morning of the third after which by -1.1 C shortly after the time of observations on the third and subsequently assigned to the 4th.  The typical minimal air temperature this month was 4.5 C, roughly 2.1 C above the corresponding most up-to-date (1991-2020) 30-year common (2.4 C).

This December there have been 11 floor frosts, that’s, days when the grass-minimum temperature was lower than or equal to zero Celsius.  The coldest three of those had been -8.0 C on the tenth, -7.6 C on the third, and -7.0 C on the ninth.  There have been 4 air frosts, these beforehand talked about (-2.9 C, -2.4 C, and -1.1 C) and -0.6 C on the ninth.

Complete precipitation this December was 43.8 mm (1.72 inches) together with 10 hint values, subsequently 43.3 mm if hint values are ignored.  That is roughly 56% of the 183-year long-term (1838-2020) common December precipitation at Armagh and 54% of the newest (1991-2020) 30-year common (81.4 mm).  This was the driest December at Armagh for 14 years, that’s, because the very chilly December 2010 (37.95 mm together with 5 hint values).

The wettest day was the sixth, with 16.0 mm (0.63 inches) of precipitation related to the arrival and passage of a quickly shifting melancholy known as storm Darragh, the fourth named storm of the 2024/2025 season. This gave heavy rain and robust winds reaching gale drive at Armagh within the small hours of Saturday seventh December.  Sturdy winds continued at Armagh all that day and into Sunday ninth December, inflicting tree harm within the Observatory grounds and energy outages throughout Northern Eire and farther afield.  The second wettest day was 7.2 mm on the thirty first, accompanied by sturdy winds approaching gale drive.  This was adopted by 6.5 mm on the fifth. 

Snow and sleet had been noticed on the morning of the nineteenth, and a rainbow was seen on the afternoon of the twentieth. 

With a complete of 29.2 hours of sturdy sunshine, roughly 77% of the 140-year long-term (1881-2020) common for December at Armagh (38.0 hours) and 68% of the newest (1991-2020) 30-year common (43.1 mm), December 2024 was a lot duller than common.  This was the dullest December at Armagh for 3 years, that’s, since December 2021 (27.8 hours of sturdy sunshine).

Calendar yr 2024 was a lot drier, a lot hotter, and barely duller than common.  With a imply annual temperature of 10.52 C, it was  roughly 1.4 C hotter than the long-term (1796-2020) common at Armagh (9.10 C) and almost 0.6 C hotter than the newest (1990-2020) 30-year common (9.94 C).  It was additionally almost 1.6 C above the standard (1850-1900) pre-industrial baseline (roughly 8.95 C at Armagh) usually used to match present and pre-industrial temperature anomalies.  2024 was the fourth warmest calendar yr on document at Armagh.  

Complete precipitation was 653.85 mm together with 73 hint values, or 650.2 mm if hint values are ignored.  That is roughly 80% of the 183-year (1838-2020) long-term annual common at Armagh (816 mm) and 79% of the newest (1991-2020) 30-year common (825 mm).  This was the twelfth driest calendar yr on document at Armagh and the driest calendar yr for 23 years, that’s, since 2001 (complete precipitation 647.45 mm together with 13 hint values).

There have been 1214.1 hours of sturdy sunshine this yr, making 2024 barely duller than common with roughly 96% of the 140-year (1881-2020) long-term common at Armagh (1261.6 hours) and 95% of the newest (1991-2020) 30-year common (1281.2 hours).  

These knowledge check with observations at Armagh Observatory, which has been recording the climate at Armagh since 1795.