Stillorgan Weather in September

September in Stillorgan averages 17°C (63°F) during the day and 11°C (52°F) at night. Quite a bit of rainfall is typical this month, with around 78 mm (3.1 in) on average. An umbrella is a good idea.

Rainfall in Stillorgan in September

Based on our climate data of the past 30 years, about 15 days of rain are anticipated, with 78 mm (3.1 in) on average. A fairly balanced picture this month, some wet days but nothing too extreme in terms of intensity.

Temperature in Stillorgan in September

Stillorgan in September gets highs of 17°C (63°F) during the day and drops to 11°C (52°F) at night. Conditions are often most pleasant around the middle of the day. At 11°C (52°F) overnight, it can feel quite a bit cooler after dark. Worth packing something warmer for evenings, but the cooler temperatures are ideal for sleeping.

Sunshine in Stillorgan in September

The month brings about 128 hours of sunlight, offering a comfortable mix of sun and overcast.

Wind Speed in Stillorgan in September

September sees wind speeds averaging 4 m/s (8 knots). You'll experience variable conditions with moderate winds that create small waves on water and keep branches moving. Conditions range from light winds to moderate breezes throughout the month.

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.

Should you favor a climate that's both dry and comfortably warm, June, July and August typically offer the most agreeable circumstances. If you're seeking pleasant, dry and sunny weather somewhere else in the world, our weather planner can help you explore other options.