Climate averages 1991–2020

Swansea weather
in June.

A mild, moderately wet month: the 3rd warmest and the 3rd driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 16.9°C Daytime mean, June

Average low 11.6°C Night-time mean, June

Rainfall 79 mm 12 days with ≥1 mm

Daylight 17 h Sunrise to sunset, per day

June is a mild month in Swansea: daytime highs average 16.9°C and nights cool to about 11.6°C. By daytime temperature it is the 3rd warmest of the 12 months.

Expect about 79 mm of rain on roughly 12 days, which makes June a moderately wet month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 16 h 34 min on an average June day.

The nearest other city in this atlas is Cardiff (55 km away). In June its highs average 17.7°C, 0.8°C warmer than Swansea, with 71 mm of rain.

Among the 143 cities listed in the United Kingdom, Swansea ranks joint 111th of 143 for the warmest June highs and joint 120th of 143 for the driest June (rainfall, lowest first). The mean June high of those 143 cities is 17.9°C; Swansea is 1.0°C cooler than that mean.

From June to July, average highs rise by 1.6°C to 18.5°C, and monthly rainfall rises from 79 mm to 86 mm.

The annual picture

June in context

30-year average

Average highAverage low°C

Monthly rainfall

Average total · mm

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Swansea climate table

1991–2020

Monthly climate averages for Swansea, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	7.7°C4.0°C	4.0°C	128	17.0	8.48 h
February	7.8°C3.7°C	3.7°C	92	13.1	9.910 h
March	9.4°C4.5°C	4.5°C	83	13.7	11.812 h
April	11.8°C6.1°C	6.1°C	69	12.0	13.814 h
May	14.6°C8.8°C	8.8°C	72	12.4	15.616 h
June, selected	16.9°C11.6°C	11.6°C	79	12.2	16.617 h
July	18.5°C13.5°C	13.5°C	86	13.8	16.216 h
August	18.5°C13.8°C	13.8°C	101	14.3	14.615 h
September	16.8°C12.1°C	12.1°C	96	13.2	12.713 h
October	13.7°C9.7°C	9.7°C	143	16.7	10.711 h
November	10.5°C6.9°C	6.9°C	143	17.3	8.99 h
December	8.2°C4.7°C	4.7°C	145	16.8	7.98 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

June in nearby cities

Distance from Swansea

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Swansea) is explained once on the Swansea year overview and on the Sources, method and limits page.