Climate and average weather in Antrim

In Antrim, the summers are mild, showery, and mostly cloudy and the winters are cold, snowy, and mostly cloudy.

Best: late May to late September

Over the course of the year, the temperature in Antrim typically varies from 3°C to 18°C, and is rarely below -1°C or above 22°C. July is the hottest month of the year, while January is the coldest.

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

Hottest
Jul
18°
Coldest
Jan
Wettest
Aug
84 mm
Driest
Feb
61 mm
Rain / yr
875 mm
166 wet days
Daylight
7.0–17.0 h
shortest–longest
Elevation
33 m
54.7°N
Clearest
May
73% cloud

Antrim is town on the shore of Lough Neagh, in the baronies of Toome Upper and Toome Lower, Co. Antrim, in the northeast of Northern Ireland.

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

Antrim 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 late May to late September.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 3.7 months, from May 30 to September 19, with daily high temperatures above 16°C. The hottest month of the year in Antrim is July, with an average high of 18°C and low of 12°C.

The cool season lasts 3.8 months, from November 19 to March 15, with daily high temperatures below 9°C. The coldest month of the year in Antrim is January, with an average low of 3°C and high of 7°C.

Days typically run about 5°C warmer than nights year-round.

-5°10°15°20°25°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan73
Feb83
Mar94
Apr115
May148
Jun1710
Jul1812
Aug1812
Sep1610
Oct138
Nov105
Dec83

How hot and cold Antrim 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 -1°C (around January 5), with roughly 96 freezing days a year (feels-like at or below 0°C), worst in January.

-5°10°15°20°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan77-13
Feb88-13
Mar9904
Apr111125
May141458
Jun1717910
Jul18181212
Aug18181212
Sep1616910
Oct131358
Nov101025
Dec8803

Average hourly temperature in Antrim

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 July afternoons, near 18°C, and coldest before dawn in January, near C.

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

Antrim 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 / 7314.21.47.60.9
Feb / 6112.61.49.31.1
Mar / 6213.90.911.51.7
Apr11° / 6513.70.213.72.6
May14° / 7014.50.115.83.6
Jun17° / 10°7714016.94.5
Jul18° / 12°8214.8016.55.0
Aug18° / 12°8414.8014.74.9
Sep16° / 10°6712.7012.54.4
Oct13° / 8113.8010.23.1
Nov10° / 7713.80.28.21.8
Dec / 7613.10.77.11.0

Chance of rain

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

Antrim gets about 875 mm of precipitation a year. On a typical day the chance of rain is very wet, and that barely changes with the seasons — rain is spread fairly evenly through the year.

August is the wettest month by volume, with 84 mm over about 15 wet days; February is the driest, with 61 mm. Some of the cold-season precipitation falls as snow.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecmostly drysome rainoften wetvery wetJul 30 · 49%Dec 16 · 40%
Rain on a day (%)Rain days
Jan4614
Feb4513
Mar4514
Apr4514
May4815
Jun4714
Jul4815
Aug4815
Sep4313
Oct4414
Nov4614
Dec4213

Monthly rainfall

Over a full year, Antrim collects about 875 mm of rain across 166 wet days — roughly 73 mm in an average month.

It doesn’t fall evenly. August is the wettest month with 84 mm, while February is the driest at just 61 mm. The three wettest months alone bring about 28% of the year’s total, and some of the cold-season precipitation falls as snow.

0255075100JanFebMarAprMayJunJulAugSepOctNovDec736162657077828467817776
Rainfall (mm)Rain daysSnow days
Jan73141
Feb61131
Mar62141
Apr65140
May70150
Jun77140
Jul82150
Aug84150
Sep67130
Oct81140
Nov77140
Dec76131

Snow in Antrim

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.

Antrim averages about 5 snowy days a year. Snow season runs roughly Nov 28 to Apr 4 — about 4.2 months.

January is snowiest, with roughly 1.4 day of snow and an estimated 6 cm of snowfall. Over the year that adds up to an estimated 18 cm of snow.

01234JanFebMarAprMayJunJulAugSepOctNovDecsnow seasonJan 15
Snow daysSnowfall (cm)
Jan16
Feb14
Mar14
Apr01
May01
Jun00
Jul00
Aug00
Sep00
Oct00
Nov01
Dec12

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

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

The clearer part of the year begins around March 28 and lasts for 2.4 months, ending around June 7. The clearest month is May, when the sky is clear, mostly clear, or partly cloudy 26% of the time on average.

The cloudier part of the year begins around June 8 and lasts for 3.5 months, ending around September 21. The cloudiest month is July, when it is overcast or mostly cloudy 86% 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 6 · 28%Jul 30 · 13%mostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan2476
Feb2278
Mar2179
Apr2575
May2674
Jun1882
Jul1486
Aug1684
Sep2080
Oct2377
Nov2476
Dec2476

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)
Jan7.68:484:20
Feb9.38:005:19
Mar11.56:516:18
Apr13.75:317:19
May15.84:278:16
Jun16.93:558:55
Jul16.54:158:46
Aug14.75:077:51
Sep12.56:066:32
Oct10.27:055:15
Nov8.28:074:13
Dec7.18:513:51

Sunny days

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

Antrim gets about 2 sunny days a month gloomy — and it barely shifts through the year, holding between 1 and 4 days every month. Clear skies here are a flat line, not a season.

0510JanFebMarAprMayJunJulAugSepOctNovDecgloomymixedMay 74 daysAug 131 days
Sunny daysSky
Jan3Gloomy
Feb3Gloomy
Mar2Gloomy
Apr3Gloomy
May4Gloomy
Jun2Gloomy
Jul2Gloomy
Aug1Gloomy
Sep2Gloomy
Oct2Gloomy
Nov3Gloomy
Dec3Gloomy

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 Antrim, the air stays dry or comfortable essentially all year. Even in August, the muggiest month, it feels humid or worse only about 4% 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 (%)Humid (%)
Jan10000
Feb10000
Mar10000
Apr10000
May9910
Jun89101
Jul69283
Aug68294
Sep86131
Oct9730
Nov10000
Dec10000

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 Antrim is typically light breeze, near 15 km/h, and varies little with the seasons.

The windier part of the year lasts 6.0 months, from around Oct 7 to Apr 7. The windiest month is January, averaging about 17 km/h (light breeze).

The calmer part of the year runs from around Apr 8 to Oct 6, with July the calmest month at about 13 km/h.

0510152025JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezyJan 10 · 17 km/hJul 20 · 13 km/h
Wind speed (km/h)Feels
Jan17light breeze
Feb17light breeze
Mar16light breeze
Apr15light breeze
May14light breeze
Jun13light breeze
Jul13light breeze
Aug13light breeze
Sep14light breeze
Oct15light breeze
Nov16light breeze
Dec16light breeze

Best time to visit Antrim

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around mid September, Antrim is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

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 Antrim for general outdoor tourist activities is from late May to late September, with a peak score in the third week of July.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJul 20 · 5.1

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
Feb1.1poor
Mar1.7poor
Apr2.6poor
May3.6fair
Jun4.5fair
Jul5.0fair
Aug4.9fair
Sep4.4fair
Oct3.1poor
Nov1.8poor
Dec1.1poor

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit Antrim for hot-weather activities is from early July to late August, with a peak score in the last week of July.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timetemperaturecloudsprecipitationJul 25 · 1.9

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 Antrim, 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 July (highs near 18°C), the essentials are rain gear and sun protection. In the cold season around January (highs near 7°C), pack a warm layer, a heavy coat and rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In July, Antrim sees daytime highs around 18°C and nights near 12°C. Pack rain gear. Worth having: sun protection. About 15 days see rain.

Sea temperature near Antrim

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 28 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 Antrim 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 Antrim 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
Jun5Moderate
Jul5High
Aug5Moderate
Sep3Moderate
Oct2Low
Nov1Low
Dec0Low

Average hourly UV index in Antrim

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
Jul6.50
Aug60
Sep20
Oct00
Nov00
Dec00
Almanac & agriculture

Growing season

Chance of a frost-free dayReliably frost-free (≥90%)

Antrim is mild enough that a frost-free day stays more likely than not even in midwinter. Nights are reliably above freezing from about March 13 to December 5 (268 days); outside that window a hard frost is an occasional risk.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecreliably frost-freeMar 1390%Dec 590%
Frost-free chance (%)Frost nights
Jan8531
Feb8528
Mar918
Apr970
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct990
Nov950
Dec8624

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. Antrim banks about 534 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.

0200400600JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan0
Feb0
Mar0
Apr0
May27
Jun100
Jul154
Aug149
Sep88
Oct15
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.

Antrim receives about 2.7 kWh/m² a day of solar energy on average — moderate — with a clear seasonal swing between 0.4 and 5.1 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 5.0 kWh/m² (bright).

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

0123456JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightJun 25.1 kWhDec 210.4 kWh
Solar energy (kWh/m²)Level
Jan0.6Dim
Feb1.3Dim
Mar2.4Moderate
Apr3.9Moderate
May5.0Bright
Jun5.0Bright
Jul4.5Bright
Aug3.8Moderate
Sep2.7Moderate
Oct1.5Dim
Nov0.8Dim
Dec0.5Dim

Where is Antrim?

Antrim sits at 54.7°N, 6.2°W, 33 m above sea level, in United Kingdom. The nearest listed city is Ballymena, 17 km away.

Topography around Antrim

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

Within 3 km, the terrain around Antrim has only modest variations in elevation — a maximum elevation change of 117 m around an average of 46 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 363 m; within 80 km, large variations in elevation — a maximum elevation change of 860 m.

The land around Antrim is covered by grassland (46%) and trees (22%) within 3 km, grassland (70%) within 16 km, and grassland (53%) and water (39%) within 80 km.

3 km
117 m
16 km
363 m
80 km
860 m
treesgrasslandcroplandartificial surfaceswater
Nearby: Ballymena 17 km · Newtownabbey 20 km · Belfast 23 km · Lisburn 24 km · Carrickfergus 26 km · Castlereagh 26 km · Larne 29 km · Craigavon 32 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 Antrim (54.7175°, -6.211°, elevation 33 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).