Climate in Northern Ireland United Kingdom
Average daytime and nighttime temperatures
All climate diagrams on this site result from the collected data from two measuring weather stations in Northern Ireland.
All data correspond to the average monthly values of the last 20 years.
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Northern Ireland is one of the coldest regions in the United Kingdom with an average daily high temperature of only 13 degrees. It rarely gets really warm up here. Due to the warmer temperatures, the best time for traveling is from July to August. Less attractive are the cold months from November to March.
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› Daylengths and sun positions in the United Kingdom
› Compare climate with other regions or countries
Sunshine hours per day
The number of hours of sunshine refers to the time when the sun is actually visible. That is, without any obstruction of visibility by clouds, fog or mountains. With 7 hours per day, May is the sunniest month in the region of Northern Ireland. In December, the sun shines the least.
Rain days per month
A rain day is a day on which at least 0.1 mm precipitation (=0.1 liter) per square meter falls. This can be rain, snow, hail or even dew. So it does not have to rain the whole day. With 18 rain days, December offers the most rain days, while April has the fewest.
Precipitation amount in mm/day
The amount of precipitation is measured in millimeters per square meter. Thus, at two mm/day, two liters of water fall on one square meter within 24 hours. With only 1.6 mm, the least amount of rain falls in April. November, on the other hand, has the most rain.
Water temperatures in °C
Water temperature depends not only on solar radiation within the same region, but also on ocean currents. For example, depending on the season, cold or warm water masses are moved from other areas. The warmest water temperatures in Northern Ireland are in August, when the water is 13 °C.
Relative humidity in %
Warm air can absorb more moisture than cold air. The relative humidity indicates how much moisture can be physically contained in the air. At high humidity, a person feels uncomfortable and perceives this as oppressive. In general, a relative humidity of 40-60% feels pleasant. With only 79% humidity on average, it is quite dry in May. The highest value of 93% is experienced here in December.
Absolute humidity in g/m³
In warm months, there is also a higher absolute humidity almost everywhere. At a temperature of 25°C, air can absorb up to 23 grams of water per cubic meter. At 20°C, it is only 17.3 grams. A relative humidity of 40% at 25°C thus corresponds to an absolute humidity of 9.2 grams of water. From a proportion of approx. 13.5 grams, humans perceive the air as muggy.
Humidex
The "Humidex" (humidity index) is an index of well-being in warmer areas, calculated from the air temperature, relative humidity and dew point. The index corresponds approximately to the temperature felt. At high temperatures, the body transports heat away by sweating. At high humidity, the ambient air can only absorb a small amount of sweat and thus one feels uncomfortable. An index of 20-29 is considered comfortable. Up to 39, people perceive the air as slightly uncomfortable, and above 40, as very uncomfortable. Values above 45 are dangerous in the long run and often lead to heat stroke.
Climate charts for other regions in the United Kingdom

Most important cities in the region »Northern Ireland«
The region has a west-east extension of about 140 km and over 130 km from north to south.City | Population | Geo position | |
---|---|---|---|
Belfast | 280,211 | 54° 34' 60"N | 5° 55' 60"W |
Derry | 83,652 | 54° 59' 53"N | 7° 18' 34"W |
Lisburn | 77,506 | 54° 31' 24"N | 6° 2' 7"W |
Newtownabbey | 63,860 | 54° 39' 35"N | 5° 54' 31"W |
Bangor | 60,385 | 54° 39' 12"N | 5° 40' 8"W |
Craigavon | 59,236 | 54° 26' 50"N | 6° 23' 13"W |
Castlereagh | 56,679 | 54° 34' 25"N | 5° 53' 5"W |
Newtownards | 29,363 | 54° 35' 32"N | 5° 41' 27"W |
Carrickfergus | 29,208 | 54° 42' 57"N | 5° 48' 21"W |
Ballymena | 28,932 | 54° 51' 49"N | 6° 16' 35"W |
Newry | 27,757 | 54° 10' 42"N | 6° 20' 15"W |
Coleraine | 25,681 | 55° 7' 60"N | 6° 40' 0"W |
Portadown | 22,000 | 54° 25' 23"N | 6° 26' 40"W |
Omagh | 21,056 | 54° 36' 0"N | 7° 17' 60"W |
Antrim | 19,661 | 54° 42' 0"N | 6° 12' 0"W |
Larne | 18,421 | 54° 51' 0"N | 5° 49' 0"W |
Banbridge | 16,173 | 54° 21' 0"N | 6° 16' 60"W |
Armagh | 14,801 | 54° 21' 0"N | 6° 40' 0"W |
Enniskillen | 14,472 | 54° 20' 46"N | 7° 38' 29"W |
Strabane | 14,198 | 54° 49' 25"N | 7° 28' 9"W |
Dundonald | 13,985 | 54° 35' 31"N | 5° 47' 53"W |
Holywood | 13,109 | 54° 38' 19"N | 5° 49' 29"W |
Limavady | 12,970 | 55° 3' 2"N | 6° 57' 3"W |
Dungannon | 11,935 | 54° 30' 12"N | 6° 46' 2"W |
Cookstown | 11,081 | 54° 38' 35"N | 6° 44' 45"W |
Downpatrick | 10,507 | 54° 19' 41"N | 5° 42' 55"W |
Ballymoney | 9,625 | 55° 4' 15"N | 6° 30' 36"W |
Ballyclare | 9,472 | 54° 46' 0"N | 6° 1' 0"W |
Comber | 9,190 | 54° 32' 58"N | 5° 44' 38"W |
Magherafelt | 9,157 | 54° 45' 13"N | 6° 36' 24"W |
Data basis: German Weather Service, individual values averaged and supplemented by own elements. Data on cities and inhabitants: geonames.org, United Nations Statistics Division and own research.