Climate averages 1991–2020

Cork weather
in September.

A mild, moderately wet month: the 4th warmest and the joint 2nd driest of the year.

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

Average high 16.7°C Daytime mean, September

Average low 11.7°C Night-time mean, September

Rainfall 64 mm 10 days with ≥1 mm

Daylight 13 h Sunrise to sunset, per day

September is a mild month in Cork: daytime highs average 16.7°C and nights cool to about 11.7°C. By daytime temperature it is the 4th warmest of the 12 months.

Expect about 64 mm of rain on roughly 10 days, which makes September a moderately wet month (the joint 2nd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 43 min on an average September day.

The nearest other city in this atlas is Limerick (86 km away). In September its highs average 16.5°C, about as warm as Cork, with 76 mm of rain.

Among the 5 cities listed in Ireland, Cork ranks 1st of 5 for the warmest September highs and 1st of 5 for the driest September (rainfall, lowest first). The mean September high of those 5 cities is 16.4°C; Cork is 0.3°C warmer than that mean.

From September to October, average highs fall by 2.9°C to 13.7°C, and monthly rainfall rises from 64 mm to 85 mm.

The annual picture

September 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

Cork climate table

1991–2020

Monthly climate averages for Cork, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	8.7°C4.7°C	4.7°C	79	13.0	8.38 h
February	8.9°C4.4°C	4.4°C	65	11.2	9.910 h
March	10.2°C5.0°C	5.0°C	62	11.8	11.812 h
April	12.2°C6.3°C	6.3°C	68	12.6	13.914 h
May	14.7°C8.8°C	8.8°C	67	13.0	15.616 h
June	17.2°C11.4°C	11.4°C	64	10.9	16.617 h
July	18.7°C13.2°C	13.2°C	67	11.8	16.216 h
August	18.5°C13.1°C	13.1°C	69	11.6	14.715 h
September, selected	16.7°C11.7°C	11.7°C	64	10.0	12.713 h
October	13.7°C9.4°C	9.4°C	85	12.4	10.711 h
November	10.8°C6.7°C	6.7°C	80	12.0	8.99 h
December	9.1°C5.3°C	5.3°C	84	12.7	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

September in nearby cities

Distance from Cork

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 Cork) is explained once on the Cork year overview and on the Sources, method and limits page.