Last updated: January 18, 2025
Northern Ireland, part of the United Kingdom, exhibits a Cfb climate classification according to the Köppen-Geiger system, characterized by its temperate maritime conditions. The region experiences minimum temperatures that can plummet to as low as -7°C (20°F) in December, reflecting the chill of winter. In contrast, the average annual temperature hovers around 10°C (50°F), providing a mild climate throughout the year. The summer peaks in June, where temperatures can reach a maximum of 29°C (84°F), highlighting a brief but warm respite from the often soggy weather that typically defines the region.
In Northern Ireland, temperature patterns reveal distinct seasonal transitions. The year begins with January and February experiencing cold conditions, with minimum temperatures often dropping to -5°C (23-24°F), and average highs only reaching 14-15°C (58-59°F). As spring approaches, particularly in March and April, a gradual warming occurs, marked by rising average temperatures and milder minimums, with April peaking at 21°C (69°F) during the day. The transition to summer in May and June brings more significant warmth, hitting maximums of 25°C (76°F) in May and 29°C (84°F) in June, alongside notably increased average temperatures. The warmth continues through July and August, where daily highs approach 28°C (83°F), while temperatures begin to moderate as autumn sets in during September. By October and November, cooler conditions prevail once again, with minimums fluctuating between -4°C and -2°C (25-29°F), heralding the return of winter, which is marked by low temperatures in December, dropping to a frigid average low of -7°C (20°F).
In Northern Ireland, Portrush experiences a minimum temperature of -1°C (31°F) in March and reaches a maximum of 19°C (67°F) in July, reflected in the monthly temperatures in Portrush. Belfast, on the other hand, sees its coldest in January at -4°C (26°F) and warms up to a maximum of 26°C (79°F) in June, as detailed in the monthly temperatures in Belfast. Meanwhile, Derry shares the same minimum of -4°C (25°F) in March, with a peak temperature of 27°C (81°F) in June, highlighted in the monthly temperatures in Derry.
Northern Ireland experiences a varying precipitation pattern throughout the year, with a notable peak in late summer and autumn. The heaviest rainfall occurs in August, averaging 123 mm (4.8 in) over approximately 18 days, making it the wettest month. This period of high precipitation is followed closely by October and November, each receiving around 103-104 mm (4.0-4.1 in) and sustaining a consistent number of rainy days. In contrast, April marks a significant decrease in rainfall, with only 48 mm (1.9 in) recorded across 10 days, suggesting a brief respite from the typically wet conditions.
Despite these fluctuations, winter months also contribute to Northern Ireland's moisture levels, with January and February receiving 69 mm (2.7 in) and 101 mm (4.0 in) respectively. Overall, while the late summer and early autumn see the highest volumes of rainfall, precipitation is a consistent feature throughout the year, with most months experiencing upwards of 80 mm (3.2 in). This steady wetness results in a lush landscape, characteristic of the region's temperate maritime climate, engaging residents and visitors alike in the unique beauty of Northern Ireland’s green vistas.
In Northern Ireland, sunshine duration illustrates a clear seasonal trend, characterized by a significant rise from the darker winter months to the brighter summer days. Beginning with a modest 76 hours in January, the amount of sunshine steadily increases, reaching 146 hours in February and 202 hours in March. By the time spring unfolds in April, sunlight balloons to 314 hours, setting the stage for the lush growth of plant life. The peak of sunshine occurs in the late spring and summer months, with May enjoying an impressive 396 hours, followed closely by June, July, and August with 385, 391, and 341 hours respectively, marking this period as the sunniest time of the year.
As the seasons transition into autumn, however, the amount of sunshine begins to decline markedly. The reduction is evident as September records 286 hours, leading to further decreases in October (224 hours) and reaching a low of just 84 hours in December. Notably, November also experiences a significant drop, with only 114 hours, reflecting the long, dim days typical of late autumn and winter. This cyclical pattern of sunshine not only shapes the region's weather but also influences its landscapes and ecosystems, showcasing the vibrant contrasts between the sunlit summers and the often overcast winter months.
The UV Index in Northern Ireland experiences notable fluctuations throughout the year, with seasonal variations reflecting the intensity of sunlight. During the winter months, specifically January and February, the UV Index remains low at 1-2, allowing for longer burn times of 45 minutes without significant risk of sunburn. As spring approaches, there is a marked increase, with March registering a moderate index of 4, encouraging more caution as burn time decreases to 30 minutes. This upward trend continues into April with a UV Index of 5, indicating the importance of protective measures as outdoor activities increase alongside the budding of spring.
The summer months of May through July showcase the highest UV levels, with indices reaching 7-8, categorized as high to very high. This period significantly reduces burn time, dropping to a quick 15-25 minutes, necessitating greater sun protection for outdoor enthusiasts. Following this peak, the index gradually declines in August (7) and September (5), signaling a return to more moderate levels, then stabilizing further into the autumn months, where values range from 3 to 2. By the time winter returns, the UV Index once again falls to 1, illustrating the cyclical nature of UV exposure in this region and emphasizing the need for mindful sun protection especially during the sunnier months.
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Daylight duration in Northern Ireland exhibits a distinct seasonal variation, reflecting the gradual shift from winter to summer and back again. In January, the days are quite short, averaging just 7 hours, which gradually increases to 9 hours in February and 11 hours in March. As spring takes hold, April sees daylight extend to 14 hours, transitioning into the longer days of summer. The peak is reached in June, with an impressive 17 hours of daylight, providing ample opportunity for outdoor activities and exploration. This abundance of light continues in July before beginning to taper off as the year progresses.
As the summer gives way to autumn, daylight duration starts to decline steadily. August still enjoys 14 hours, but this falls to 12 hours in September and continues to decrease throughout the autumn months, reaching 10 hours in October. By November, daylight is reduced to 8 hours, and winter heralds a return to 7 hours in December. This cyclical pattern of daylight hours profoundly influences daily life and seasonal activities in Northern Ireland, dictating not just the rhythms of nature but also the lifestyle choices of those who inhabit the region.
Antrim, United Kingdom experiences a temperate maritime climate characterized by mild winters and cool summers. Temperatures range from a harsh low of -4°C (25°F) in January to a pleasant high of 27°C (80°F) in July. Precipitation is fairly consistent throughout the year, peaking in August with 118 mm (4.7 in) of rainfall, while sunshine hours are at their highest in May with 402 hours. Overall, Antrim enjoys a balance of wet and dry spells, ideal for its lush landscapes. For more detailed information, visit Antrim climate.
Armagh, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and significant rainfall throughout the year. Winter months see average temperatures ranging from 5°C in January to 7°C in November, while summer peaks occur in July with averages around 16°C. Precipitation is heaviest in August with 121 mm, while sunshine peaks in May with an impressive 365 hours. Overall, Armagh offers a mix of cool, wet winters and mild, sunny summers, making it an interesting place to experience varied weather patterns. For more detailed information, visit Armagh climate.
Ballintoy Harbour experiences a temperate maritime climate characterized by mild summers and cool winters. Average temperatures range from a low of 1°C (34°F) in February to a high of 19°C (66°F) in July. Rainfall is prevalent, with the wettest months being November and October, receiving around 167 mm (6.6 in) and 160 mm (6.3 in) respectively. Sunshine hours peak in May and July, with 408 and 410 hours, making these the sunniest months of the year. For more detailed information, visit the Ballintoy Harbour climate page.
The climate in Ballycastle, United Kingdom, features mild temperatures with distinct seasonal variations. Winters are cool, with average temperatures around 7°C (45°F) in January, while summers can reach up to 19°C (66°F) in July. Precipitation is notable, particularly in late autumn and winter months, with November experiencing the highest levels at 167 mm (6.6 in). Sunshine hours peak in the summer, offering up to 410 hours in July, contrasting sharply with the lower totals in winter. For more detailed information, visit Ballycastle climate.
Bangor, United Kingdom, experiences a temperate maritime climate, characterized by mild temperatures and varying precipitation throughout the year. January sees average temperatures around 6°C (44°F) with significant rainfall, peaking in February at 111 mm (4.4 in). The warmest months, July and August, reach averages of 14°C (58°F) and 14°C (58°F), respectively, accompanied by high sunshine hours, particularly in July with 415 hours. Rainfall is frequent, especially during late summer to autumn, making May to September the driest months. For more details, visit Bangor climate.
Belfast experiences a temperate maritime climate with mild summers and cool winters. January sees average temperatures around 6°C (43°F) with substantial precipitation peaking in August at 115 mm (4.5 in). Sunshine hours are highest in May and June, offering over 400 hours of sun, while the year’s shortest days occur in December with only 87 hours. Rainfall remains relatively consistent throughout the year, making an umbrella a necessary accessory year-round. For more details, visit Belfast climate.
Bushmills, United Kingdom experiences a temperate maritime climate with mild temperatures throughout the year. The coldest months are January to March, with average temperatures between 7°C (45°F) and a maximum of 13°C (56°F). Precipitation is fairly consistent, peaking in late autumn and winter, with November and December recording over 160 mm (6.3 in) of rain. Sunshine is most abundant in late spring and summer, reaching up to 410 hours in July. For detailed climate data, visit Bushmills climate.
Carrickfergus, United Kingdom, experiences a temperate maritime climate with mild temperatures throughout the year. January and February are the coldest months, with average temperatures around 6°C (43°F) and substantial rainfall peaking at 111 mm (4.4 in) in February. Summer months from June to August bring warmer temperatures, averaging between 13°C (55°F) and 14°C (58°F), while also receiving significant sunshine, with July seeing up to 415 hours of sunlight. Precipitation is common, particularly in late summer and autumn, culminating with 129 mm (5.1 in) in August and 128 mm (5.1 in) in November. For more details on the weather patterns, visit Carrickfergus climate.
The climate in Castlerock, United Kingdom, features mild temperatures with a significant range throughout the year. Winter months see average temperatures around 7°C (45°F), with January being the coldest. Rainfall is quite prominent, especially in late autumn and winter, peaking at 166 mm (6.5 in) in December. Sunshine hours increase substantially from spring into summer, with May averaging 405 hours. For more detailed information, visit Castlerock climate.
Castlewellan, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and considerable rainfall throughout the year. The warmest months are July and August, with average temperatures around 15°C (59°F) and maximums reaching 24°C (76°F), while January is the coldest month, with averages of 6°C (43°F) and maximums of 13°C (56°F). Rainfall is most abundant in August and November, averaging about 120 mm (4.7 in) and 113 mm (4.5 in), respectively. Sunlight peaks in May with 403 hours, while winter months see significantly less sunshine. For more details, visit Castlewellan climate.
Coleraine, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and significant rainfall throughout the year. Average temperatures range from a chilly 7°C (45°F) in winter to a pleasant 14°C (58°F) in summer, with July and August being the warmest months. Precipitation peaks in late autumn and winter, particularly in December (166 mm) and October (161 mm), while the driest month is April (55 mm). Sunshine hours vary greatly, with May enjoying the most at 405 hours, contrasting sharply with January's 72 hours. For more detailed information, visit Coleraine climate.
Cushendall, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and ample rainfall throughout the year. January and February are the coldest months, with average temperatures of around 6°C (43°F), while July typically sees the highest average temperature of 15°C (59°F). Rainfall is heaviest in the summer, particularly in August, averaging 128 mm (5.0 in), while sunshine peaks in May and July, with about 412 and 418 hours respectively. This combination of weather creates a lush and vibrant environment in Cushendall, making it a picturesque destination. For more details, visit Cushendall climate.
Derry, United Kingdom experiences a temperate maritime climate, with average temperatures ranging from a chilly 6°C (42°F) in winter months to a warm 15°C (59°F) during summer. The wettest months are typically February and August, receiving up to 134 mm (5.3 in) of precipitation, while April tends to be the driest. Sunshine hours peak in May with about 400 hours, contributing to a mild and pleasant late spring. Overall, Derry's climate is characterized by moderate temperatures, substantial rainfall, and seasonal variation. For more details, visit Derry climate.
Donaghadee, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and considerable rainfall throughout the year. The average monthly temperatures range from a chilly 7°C (45°F) in winter to a more pleasant 14°C (57°F) during the summer months. Precipitation is highest in late autumn, with November receiving about 147 mm (5.8 in) of rain, and sunshine peaks in the summer, particularly in July with 415 hours. Despite its relatively rainy weather, Donaghadee enjoys a generous amount of sunshine in the spring and summer, making it an inviting locale for outdoor activities. For more detailed information, visit Donaghadee climate.
Downpatrick, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and frequent precipitation. Winter months like January and February see average temperatures around 6-7°C (44-45°F) with considerable rainfall, peaking in November at 120 mm (4.7 in). As spring progresses, temperatures gradually rise, reaching highs of up to 24°C (75°F) in July, while sunshine hours peak in May and June, totaling over 400 hours. Rainfall is also significant in late summer and early autumn, with August receiving about 115 mm (4.5 in). For more details, visit Downpatrick climate.
Enniskillen experiences a temperate maritime climate with distinct seasonal variations. Winters are chilly, with January lows reaching -5°C (24°F), while summers can warm up to around 29°C (84°F) in June. Precipitation is prevalent, particularly in late winter and summer, with August being the wettest month at 143 mm (5.6 in). The region enjoys the most sunshine in May and June, with total hours exceeding 360, providing a bright contrast to the cloudy winter months. For more detailed information, visit Enniskillen climate.
Glenariff, United Kingdom experiences a temperate maritime climate with mild winters and moderately warm summers. Average temperatures range from a minimum of -3°C (27°F) in March to a maximum of 24°C (76°F) in July. Precipitation is fairly consistent throughout the year, peaking in August at 128 mm (5.0 in), while sunshine hours are most abundant in May and July, reaching up to 412 and 418 hours respectively. The region sees higher rainfall in the winter months, particularly in February with 101 mm (4.0 in). For more detailed information, visit Glenariff climate.
Holywood, United Kingdom, experiences a temperate maritime climate with mild temperatures throughout the year. Average temperatures range from 6°C (44°F) in winter to a mild 14°C (58°F) in summer, with July being the warmest month. Rainfall is moderate, peaking in August and November, while April and May tend to be drier. The area enjoys a fair amount of sunshine, particularly in late spring and summer, with May and July receiving the most hours. For more details on the climate, visit Holywood climate.
Lisburn, United Kingdom experiences a temperate maritime climate characterized by mild temperatures and variable precipitation throughout the year. January marks the coldest month with temperatures ranging from -4°C to 14°C, while July sees the warmest conditions, with temperatures from 8°C to 26°C. The city receives its highest rainfall in August (115 mm) and lowest in April (45 mm), with annual sunshine peaking in May (403 hours). Overall, Lisburn's climate offers balanced seasons ideal for various outdoor activities. For more detailed information, visit Lisburn climate.
Newcastle experiences a temperate maritime climate, with average temperatures ranging from -2°C (29°F) in January to 24°C (75°F) in July. Precipitation is relatively high, particularly in August, with an average of 120 mm (4.7 in) of rainfall. The city enjoys the most sunshine in May, totaling 403 hours, while December sees the least at just 87 hours. Overall, Newcastle's climate features distinct seasons with noticeable variations in temperature and rainfall throughout the year. For more detailed information, visit Newcastle climate.
Newry, United Kingdom, experiences a temperate maritime climate with mild temperatures throughout the year. January sees minimum temperatures drop to -5°C (23°F), gradually warming to a maximum of 28°C (82°F) in July. Rainfall is prevalent, particularly in the summer months, with August being the wettest at 113 mm (4.4 in). Despite the precipitation, the area enjoys significant sunshine, peaking in May with 383 hours. For more details, visit Newry climate.
Portaferry, United Kingdom experiences a temperate maritime climate, with mild winters and cool summers. January and February are typically the coldest months, with average temperatures around 7°C (45°F) and significant rainfall, peaking in November with 123 mm (4.9 in). The summer months of June to August are the warmest, with average temperatures reaching about 15°C (59°F) and relatively high sunshine hours, particularly in May with 411 hours. Overall, Portaferry sees considerable precipitation throughout the year, maintaining lush greenery. For more detailed climate information, visit Portaferry climate.
Portrush, United Kingdom, experiences a temperate maritime climate characterized by cool temperatures and considerable rainfall throughout the year. The average temperature ranges from a low of 2°C in January to a high of 19°C in July, while precipitation peaks in December at 166 mm. Sunshine hours vary, with May and July boasting the most at around 405 hours, while January offers only 72 hours. Overall, Portrush displays a mix of wet and dry months, making it an intriguing destination for visitors. For more detailed information, visit Portrush climate.
The climate in Portstewart, United Kingdom, features mild temperatures throughout the year, with January averaging around 7°C (45°F) and July peaking at about 14°C (57°F). Rainfall is relatively high, particularly in late autumn and winter, with October and December recording over 160 mm (6.3 in) of precipitation. Sunshine hours are plentiful during the summer months, notably in May and July, while winter months see significantly less sunlight. This combination of mild temperatures and frequent rain contributes to Portstewart's lush landscapes. For more detailed information, visit Portstewart climate.
Rostrevor, United Kingdom, experiences a temperate maritime climate characterized by mild temperatures and abundant rainfall. Monthly average temperatures range from a chilly 6°C (43°F) in January to a warm 16°C (61°F) in July, with maximums occasionally reaching 27°C (80°F). Precipitation is notably higher in late summer and autumn, peaking at 111 mm (4.4 in) in August. The sunnier months are May and June, boasting over 370 hours of sunshine, while January is the gloomiest with only 79 hours. For more detailed information, visit Rostrevor climate.
In conclusion, the climate of Northern Ireland is characterized by its temperate maritime conditions, marked by distinct seasonal variations in temperature, precipitation, sunshine duration, UV Index, and daylight hours. The region experiences mild winters and warm summers, with a notable increase in rainfall during the autumn months, reflecting its lush green landscapes. As day length increases from winter to summer, residents enjoy longer hours of sunshine, particularly during the peak summer months. Understanding these climatic trends not only enhances appreciation for the natural beauty of Northern Ireland but also informs residents and visitors about the importance of sun protection during high UV Index periods and prepares them for the unique weather patterns throughout the year. This comprehensive climate profile serves as a valuable resource for recognizing the environmental factors that shape life in this dynamic region.