Cork Weather in September

September in Cork brings moderate temperatures around 18°C (64°F) during the day, dropping to 12°C (54°F) at night, with quite a bit of rainfall expected, averaging around 77 mm (3 in) for the month.

Rainfall in Cork in September

Historically, approximately 17 days this month are expected to have rain, averaging 77 mm (3 in). Expect plenty of grey, overcast days rather than intense storms. The rain rarely amounts to much on any given day.

Temperature in Cork in September

In September, Cork sees moderate temperatures, with highs of 18°C (64°F). Nights drop to around 12°C (54°F). Temperatures can feel cooler in the morning and evening, so layering is often the best approach. With overnight lows of 12°C (54°F), evenings can feel noticeably cooler than the daytime. An extra layer is a good idea, though the cool air makes for a good night's sleep.

Sunshine in Cork in September

You can expect a moderate amount of sunlight, with approximately 128 hours. This means a pleasant mix of sun and overcast.

Wind Speed in Cork in September

Average wind conditions reach 5 m/s (10 knots) in September. This creates lively weather with fresh winds that make small trees sway noticeably. Remember this is an average: some days are less windy while others have particularly active windy conditions.

Average water temperature in September

The water temperature is 15°C (59°F) — chilly, but perfectly fine for a swim if you're not too sensitive to cold water. A short wetsuit can make longer sessions more comfortable.

If you favor pleasant temperatures and minimal rainfall, September is one of the best months to visit Cork.

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Check the conditions for any month of the year.

• January
• February
• March
• April

• May
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• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Ireland, check out our Cork's climate page.

Cork Temperature in September

Min Temperature 12°C (54°F)  

Max Temperature 18°C (64°F)  

Water Temperature 15°C (59°F)  

Chance of Rain 57%  

Precipitation 77 mm (3 in)  

Rainy days 17 days  

Humidity 75%  

Windspeed 5 m/s (10 knots)  

Sunshine 128 hours  

Percentage Sunshine 33%  

Daily Historical Temperatures

50-year average (1976-2025)

Based on our historical records, temperatures in Cork typically stay consistent throughout September, with daily highs averaging around 18°C (64°F). Nights are cool, with lows typically ranging from 9°C (48°F) to 12°C (54°F).

Average temperatures in September

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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Daily Historical Precipitation

50-year average (1976-2025)

Average daily rainfall for each day of the month based on long-term records.

Average precipitation in September

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Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

‹ January February March April May June July August September October November December ›

Historical weather for Cork in September

Browse day-by-day weather records for Cork spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.

Historical weather Temperatures Precipitation

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‹ January February March April May June July August September October November December ›

Cork historical weather extremes in September

Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Cork.

• The warmest day in September was on September 2, 1991, with a maximum of 25°C (77°F).
• Cork experienced its chilliest September day on September 20, 2018, reaching only 10°C (50°F).
• The lowest overnight temperature recorded in September was 3°C (37°F) (September 15, 1986).

What to Wear in Cork in September

Comfortable temperatures call for an easy wardrobe in September. Pack summer basics like t-shirts and shorts, but include a light jacket for cooler moments. A pair of comfortable walking shoes is essential. Wet weather is likely, so pack waterproof gear for multiple rainy days. Expect water temperatures of around 15°C (59°F), which is definitely too cold for comfortable swimming. Your luggage space is better used for other items. It won't hurt to bring your sunglasses along, as you'll see some sunny periods.

What To Do in Cork in September

We rated the following activities from 1 (least suitable) to 10 (best) to do.

Swimming

6/10

Cycling

6/10

Walking

6/10

Camping

8/10

Outdoor sports

9/10

Select a Month

Check the conditions for any month of the year.

• January
• February
• March
• April

• May
• June
• July
• August

• September
• October
• November
• December

For a detailed overview over the year and the best time to visit Ireland, check out our Cork's climate page.

More climate data for Cork

Temperature Rainfall Sunshine Humidity Wind Speed Water Temp

See the full Cork climate overview or explore weather in Ireland.