See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
13°
Drizzle
Feels Like: 12°
Min: 12°
Max: 16°
The next few hours will be overcast, with today reaching 16°C and dropping to 11°C. The coming days will be drizzle until night.
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
07:26
Sunrise
19:06
Sunset
Moon
Waxing Gibbous
18:41
Moonrise
05:37
Moonset
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View stargazing scoreWeather in Castleknock today, September 25, 2026
Castleknock starts September 25, 2026 looking damp, with rain in the forecast and wetter spells likely at times. Waterproof kit is the safer call for early plans. Early hours look the most unsettled, with rain probability near 60% by 07:00. The thickest cloud arrives around 07:00, reaching about 100%.
The day peaks near 16°C and cools toward 12°C. The air stays humid, with relative humidity between 65% and 91% and the peak around 07:00. Winds stay light, near 3.9 km/h by 15:00, so the day feels still more than breezy.
Later hours look less wet than the morning, when rain odds were closer to 60%; afternoon chances sit nearer 0%. Residual cloud near 100% around 13:00 may linger. Horizontal visibility sits around 32.1 km, briefly nearer 16.1 km. Sunrise is at 07:26 and sunset at 19:06, giving 11 hours 40 minutes of sunlight today.
The practical takeaway for Castleknock on September 25, 2026 is simple: plan for rain, keep layers handy, and work around a high of about 16°C.
Frequently asked questions about weather in Castleknock
How warm does it get in Castleknock?
The warmest month in Castleknock is July, with average high temperatures of 18°C. The average temperature during this period is around 16°C.
How cold does it get in Castleknock?
The coldest month in Castleknock is January, with average low temperatures of 3°C. The average temperature during this period is around 5°C.
What is the wettest time of year in Castleknock?
The wettest month in Castleknock is September, with an average of 94mm of precipitation.
What is the driest time of year in Castleknock?
The driest month in Castleknock is May, with an average of 64mm of precipitation.
