The Armagh Observatory has reported that January was sunnier than average, but cooler and slightly wetter than average.
The number of hours of strong sunshine was 67.5, approximately 45 percent more hours than the most recent 30-year (1981–2010) average for January at Armagh.
This was the sunniest January for four years, that is, since January 2011. The sunniest day was the 6th with 5.8 hours of strong sunshine.
The mean monthly temperature was approximately 3.8 degrees Celsius (38.9 degrees Fahrenheit), nearly 0.9 degrees C cooler than the most recent 30-year (1981–2010) average January temperature of 4.7 C. This month was also the coolest January since 2011.
Despite this, there were a couple of very warm days: the 1st (maximum air temperature 13.6 C) and the 9th (maximum air temperature 13.7 C). The latter was the warmest January day for seven years, that is, since 18th January 2008.
The coldest day was the 19th with a lowest maximum air temperature of 2.2 degrees C. This was also the coolest night, with a lowest minimum air temperature of minus 4.5 C. The 19th also registered the lowest minimum ground temperature, namely minus 10.8 degrees Celsius. There were 22 nights with grass frost and 17 with air frost.
Total precipitation for the month was 85.55 mm (approximately 3.4 inches), approximately 15 percent more than the most recent 30-year (1981–2010) average January rainfall at Armagh. The two wettest days were the 14th and 28th, each with 9.7 mm (0.38 inches) of rainfall. During the month, there were only two days with no recorded precipitation at all.