Climate and average weather in Carrickfergus

In Carrickfergus, the summers are mild, wet, and mostly cloudy and the winters are cold, breezy, snowy, and mostly cloudy.

Best: early June to late September

Over the course of the year, the temperature in Carrickfergus typically varies from 5°C to 16°C, and is rarely below 2°C or above 18°C. August is the hottest month of the year, while February is the coldest.

Based on the travel score, the best time of year to visit Carrickfergus for warm-weather activities is from early June to late September.

Hottest
Aug
16°
Coldest
Feb
Wettest
Oct
114 mm
Driest
Apr
68 mm
Rain / yr
1082 mm
180 wet days
Daylight
7.0–17.0 h
shortest–longest
Elevation
7 m
54.7°N
Clearest
May
67% cloud

Carrickfergus is town in County Antrim, Northern Ireland.

Density
2,386/km²
people per km²

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Carrickfergus weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early June to late September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in Carrickfergus, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

The hot season lasts 3.6 months, from June 16 to October 1, with daily high temperatures above 14°C. The hottest month of the year in Carrickfergus is August, with an average high of 16°C and low of 13°C.

The cool season lasts 4.3 months, from November 29 to April 8, with daily high temperatures below 9°C. The coldest month of the year in Carrickfergus is February, with an average low of 5°C and high of 7°C.

Days typically run about 3°C warmer than nights year-round.

10°15°20°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan85
Feb75
Mar85
Apr106
May128
Jun1411
Jul1512
Aug1613
Sep1512
Oct1210
Nov107
Dec85

How hot and cold Carrickfergus really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the coldest nights, wind chill pulls the feels-like down to about -0°C (around February 27), with roughly 36 freezing days a year (feels-like at or below 0°C), worst in February.

-5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan7805
Feb7705
Mar8815
Apr91036
May121258
Jun14141011
Jul15151212
Aug16161313
Sep15151212
Oct1212810
Nov101037
Dec8815

Average hourly temperature in Carrickfergus

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on August afternoons, near 16°C, and coldest before dawn in February, near C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

Carrickfergus weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / 9917.20.87.60.9
Feb / 791419.30.9
Mar / 7614.60.711.51.2
Apr10° / 6813.40.213.71.8
May12° / 7213.5015.82.7
Jun14° / 11°8213.7016.93.5
Jul15° / 12°9415.4016.54.0
Aug16° / 13°9215.1014.74.2
Sep15° / 12°8613.8012.53.8
Oct12° / 10°11416.2010.22.8
Nov10° / 11317.30.18.21.8
Dec / 10915.70.47.11.2

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

Carrickfergus gets about 1082 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 2.5 months, from around Sep 29 to Dec 12, peaking in November at about 58% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Apr 13.

October is the wettest month by volume, with 114 mm over about 16 wet days; April is the driest, with 68 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%70%JanFebMarAprMayJunJulAugSepOctNovDecdrierwettermostly drysome rainoften wetvery wetNov 15 · 58%Apr 13 · 42%
Rain on a day (%)Rain days
Jan5517
Feb5014
Mar4715
Apr4413
May4414
Jun4614
Jul4915
Aug4915
Sep4714
Oct5216
Nov5717
Dec5116

Monthly rainfall

Over a full year, Carrickfergus collects about 1082 mm of rain across 180 wet days — roughly 90 mm in an average month.

It doesn’t fall evenly. October is the wettest month with 114 mm, while April is the driest at just 68 mm. The three wettest months alone bring about 31% of the year’s total, and some of the cold-season precipitation falls as snow.

0255075100125150JanFebMarAprMayJunJulAugSepOctNovDec997976687282949286114113109
Rainfall (mm)Rain daysSnow days
Jan99171
Feb79141
Mar76151
Apr68130
May72140
Jun82140
Jul94150
Aug92150
Sep86140
Oct114160
Nov113170
Dec109160

Snow in Carrickfergus

Average snowy days through the year, the snow-season span, and estimated snowfall — for ski trips and the perennial 'will there be snow at Christmas?' question.

Carrickfergus averages about 3 snowy days a year. Snow season runs roughly Dec 31 to Mar 13 — about 2.4 months.

February is snowiest, with roughly 1.0 day of snow and an estimated 3 cm of snowfall. Over the year that adds up to an estimated 12 cm of snow.

01234JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonFeb 26
Snow daysSnowfall (cm)
Jan13
Feb13
Mar13
Apr00
May00
Jun00
Jul00
Aug00
Sep00
Oct00
Nov00
Dec02

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In Carrickfergus, the average share of the sky covered by clouds shows mild seasonal variation over the course of the year.

The clearer part of the year begins around March 24 and lasts for 2.7 months, ending around June 13. The clearest month is May, when the sky is clear, mostly clear, or partly cloudy 34% of the time on average.

The cloudier part of the year begins around June 14 and lasts for 2.3 months, ending around August 21. The cloudiest month is July, when it is overcast or mostly cloudy 76% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecMay 4 · 38%Aug 1 · 23%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2773
Feb2773
Mar2773
Apr3466
May3466
Jun2872
Jul2476
Aug2674
Sep2872
Oct2773
Nov2674
Dec2773

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 13, brings about 17 hours of light; the shortest, around December 13, only 7 hours — a swing of roughly 10 hours.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan7.68:464:19
Feb9.37:585:17
Mar11.56:496:16
Apr13.75:307:17
May15.84:258:14
Jun16.93:548:53
Jul16.54:138:45
Aug14.75:067:49
Sep12.56:046:31
Oct10.27:035:14
Nov8.28:064:11
Dec7.18:493:49

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

Carrickfergus averages about 4 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 2 and 6 days.

The sunnier stretch runs 2.7 months, from around Mar 23 to Jun 11. The sunniest month is May, with roughly 5 sunny days (gloomy).

The greyest month is August, down near 3 sunny days — about 52% fewer than the May peak.

0510JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedMay 46 daysAug 32 days
Sunny daysSky
Jan4Gloomy
Feb3Gloomy
Mar4Gloomy
Apr5Gloomy
May5Gloomy
Jun3Gloomy
Jul3Gloomy
Aug3Gloomy
Sep3Gloomy
Oct3Gloomy
Nov4Gloomy
Dec4Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

In Carrickfergus, the air stays dry or comfortable essentially all year. Even in August, the muggiest month, it feels humid or worse only about 0% of the time — humidity is not something you need to plan around here.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDeccomfortabledry
Dry (%)Comfortable (%)
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun973
Jul8119
Aug7327
Sep8812
Oct982
Nov1000
Dec1000

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Across the year, average wind speed in Carrickfergus is typically breezy, near 21 km/h, and varies moderately with the seasons.

The windier part of the year lasts 6.1 months, from around Sep 30 to Apr 2. The windiest month is January, averaging about 25 km/h (breezy).

The calmer part of the year runs from around Apr 3 to Sep 29, with July the calmest month at about 16 km/h.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezywindyJan 8 · 25 km/hJul 21 · 16 km/h
Wind speed (km/h)Feels
Jan25breezy
Feb24breezy
Mar22breezy
Apr20light breeze
May18light breeze
Jun17light breeze
Jul16light breeze
Aug17light breeze
Sep20light breeze
Oct22breezy
Nov24breezy
Dec25breezy

Best time to visit Carrickfergus

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in Carrickfergus throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around mid June, Carrickfergus is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit Carrickfergus for general outdoor tourist activities is from early June to late September, with a peak score in the second week of August.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationAug 10 · 4.2

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan0.9poor
Feb0.9poor
Mar1.2poor
Apr1.8poor
May2.7poor
Jun3.5poor
Jul4.0fair
Aug4.1fair
Sep3.8fair
Oct2.8poor
Nov1.8poor
Dec1.2poor

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Carrickfergus rarely gets warm enough to lift this score — no time of year really suits hot-weather activities here.

024681012JanFebMarAprMayJunJulAugSepOctNovDectemperaturecloudsprecipitation

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for Carrickfergus, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

For a warm-season trip around August (highs near 16°C), the essentials are a warm layer and rain gear. In the cold season around February (highs near 7°C), pack a warm layer, a heavy coat, rain gear and a windbreaker.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Carrickfergus sees daytime highs around 16°C and nights near 13°C. Pack rain gear. Worth having: a warm layer. About 15 days see rain.

Sea temperature near Carrickfergus

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea at the nearest coast (about 18 km away) is warmest in September at about 14°C and coldest in March near 8°C.

The water stays below 20°C all year — cool enough that most swimmers want a wetsuit.

6°8°10°12°14°16°JanFebMarAprMayJunJulAugSepOctNovDecbracingcool
Sea temperature (°C)Comfort
Jan9Bracing
Feb8Bracing
Mar8Bracing
Apr8Bracing
May9Bracing
Jun11Bracing
Jul12Bracing
Aug13Bracing
Sep14Bracing
Oct14Bracing
Nov12Bracing
Dec11Bracing

UV index (midday) in Carrickfergus by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in Carrickfergus peaks around May 22 at about 5 (high) — a little sun protection helps at midday. It bottoms out near January 1 at about 0 (low).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 5 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecLowModerateHighModerateLowMay 22UV 5Jan 1UV 0
UV index (midday)Level
Jan0Low
Feb1Low
Mar2Moderate
Apr3Moderate
May5High
Jun5High
Jul5High
Aug5Moderate
Sep3Moderate
Oct2Low
Nov1Low
Dec0Low

Average hourly UV index in Carrickfergus

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in May the burn window is concentrated in the middle of the day: about 6.5 hours a day reach index 3 (protection recommended). Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan00
Feb00
Mar00
Apr00
May6.50
Jun6.50
Jul70
Aug60
Sep20
Oct00
Nov00
Dec00
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Carrickfergus is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan990
Feb990
Mar990
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec990

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Carrickfergus banks about 449 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

0200400600JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr0
May9
Jun65
Jul119
Aug130
Sep94
Oct32
Nov0
Dec0

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

Carrickfergus receives about 2.7 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.4 and 5.2 kWh/m².

The brighter stretch of the year lasts 5.8 months, from around Mar 23 to Sep 16. The brightest month is June, averaging about 5.1 kWh/m² (bright).

The dimmest month is December, down near 0.5 kWh/m² — roughly 91% less than the June peak.

0123456JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightJun 35.2 kWhDec 220.4 kWh
Solar energy (kWh/m²)Level
Jan0.6Dim
Feb1.3Dim
Mar2.5Moderate
Apr4.0Moderate
May5.1Bright
Jun5.1Bright
Jul4.7Bright
Aug3.9Moderate
Sep2.8Moderate
Oct1.6Dim
Nov0.8Dim
Dec0.5Dim

Where is Carrickfergus?

Carrickfergus sits at 54.7°N, 5.8°W, 7 m above sea level, in United Kingdom. The nearest listed city is Newtownabbey, 9.0 km away.

Topography around Carrickfergus

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Carrickfergus.

Within 3 km, the terrain around Carrickfergus has only modest variations in elevation — a maximum elevation change of 171 m around an average of 25 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 447 m; within 80 km, large variations in elevation — a maximum elevation change of 860 m.

The land around Carrickfergus is covered by water (47%) and grassland (25%) within 3 km, grassland (46%) and water (30%) within 16 km, and water (49%) and grassland (43%) within 80 km.

3 km
171 m
16 km
447 m
80 km
860 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Newtownabbey 9.0 km · Bangor 11 km · Larne 15 km · Belfast 15 km · Newtownards 16 km · Castlereagh 17 km · Lisburn 26 km · Antrim 26 km

United Kingdom travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type D / G / M
230 V · 50 Hz
Prices
≈ 89% of US
price level, 2025
GDP per capita
$57,602
2025
Happiness
6.7 / 10
World Happiness, 2025
Safe drinking water
100%
of population, 2024
Homicide rate
1.1
per 100k, 2021
Road deaths
3.2
per 100k/yr, 2019
Income group
High
World Bank
Religion
Christian 60%none 26%Muslim 4%other 2%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Carrickfergus (54.7158°, -5.8058°, elevation 7 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).