Castlerock in september: average Weather, Temperature and Climate
Weather in Castlerock in september 2025
The weather in Castlerock in september comes from statistical datas on the last years. You can view the weather statistics for the whole month, but also navigating through the tabs for the beginning, the middle and the end of the month.
Average weather throughout september
tolerable weather
Weather at 6am
54°F
Partly Cloudy
25% of time
24%
22%
17%
Weather at 12pm
59°F
Moderate rain at times
35% of time
22%
21%
15%
Weather at 6pm
58°F
Moderate rain at times
38% of time
21%
16%
15%
Weather at 3am
54°F
26%
24%
19%
19%
Evolution of daily average temperature and precipitation in Castlerock in september
These charts show the evolution of average minimum/maximum temperatures as well as average daily precipitation volume in Castlerock in september.
The climate of Castlerock in september is tolerable
In september in Castlerock, the climate is wet (with 4.1in of precipitation over 7 days). The weather is better from the previous month since in august it receives an average of 5.9in of precipitation over 10 days.
The climate is quite fresh here september, but it is livable by dressing cosy. Temperatures are up to 61°F. The seasonal minimum is 54°F. Thus, the mean temperature average in september in Castlerock is 58°F. Note that seasonal normals in contrast with those observed in Castlerock in september with a maximum record of 70°F in 2021 and a minimum record of 41°F in 2010. You can hope to have about 3 days with temperatures above 65°F, or 10% of the month.
Day length in Castlerock in september is 12:44. The sun rises at 06:00 and sunset is at 18:44.
With a correct climate, september is okay (but not good) to go in Castlerock in North Ireland.
September: another location in Northern Ireland?
If you want to go to Northern Ireland in september, there are destinations with better weather than Castlerock:
In september, Donwpatrick, Larne, Annalong, Bangor, Carrickfergus and Dundrum have good weather.
Seasonal average climate and temperature of Castlerock in september
Check below seasonal norms These statistics are generated from the weather statements of the last years of the month of september.
| September | |||||
| Outside temperature | |||||
| Average temperature | 58°F | ||||
| Highest temperature | 61°F | ||||
| Lowest temperature | 54°F | ||||
| Highest record temperature | 70°F (2021) | ||||
| Lowest record temperature | 41°F (2010) | ||||
| Number of days at +65°F | 3 day(s) (10%) | ||||
| Sea temperature | |||||
| Average sea temperature | 58°F | ||||
| Lowest sea temperature | 57°F | ||||
| Highest sea temperature | 60°F | ||||
| Wind | |||||
| Wind speed | 26km/h | ||||
| Wind temperature | 50°F | ||||
| Precipitation (rainfall) | |||||
| Rainfall | 4.1in | ||||
| Number of days with rainfall | 7 day(s) (24%) | ||||
| Record daily rainfall | 1.1in (2017) | ||||
| Other climate data | |||||
| Humidity | 90% | ||||
| Visibility | 8.97km | ||||
| Cloud cover | 58% | ||||
| UV index | 4 | ||||
| Daily sunshine hours | 10 | ||||
| Sunrise and sunset | |||||
| Time of sunrise | 06:00 | ||||
| Time of sunset | 18:44 | ||||
| Length of day | 12:44 | ||||
| Our opinion about the weather in september | |||||
| Our opinion at whereandwhen.net | tolerable | ||||
How was the weather last september?
Here is the day by day recorded weather in Castlerock in september 2024:
58°F to 59°F
58°F to 59°F
56°F to 58°F
56°F to 58°F
56°F to 58°F
59°F to 61°F
59°F to 61°F
56°F to 58°F
56°F to 58°F
54°F to 58°F
52°F to 54°F
52°F to 54°F
50°F to 54°F
56°F to 61°F
58°F to 59°F
54°F to 61°F
58°F to 63°F
58°F to 61°F
56°F to 61°F
58°F to 59°F
58°F to 61°F
56°F to 59°F
54°F to 58°F
52°F to 56°F
50°F to 52°F
50°F to 54°F
52°F to 54°F
50°F to 56°F
52°F to 56°F
50°F to 54°F
Map: other cities in Northern Ireland in september
Cities near Castlerock:
| Portstewart in september | tolerable weather |
| Coleraine in september | tolerable weather |
| Portrush in september | tolerable weather |
| Limavady in september | tolerable weather |
| Ballymoney in september | tolerable weather |
| Maghera in september | tolerable weather |
| Ballycastle (Causeway Coast) in september | tolerable weather |
| Derry (Londonderry) in september | tolerable weather |
| Ballymena in september | tolerable weather |
| Magherafelt in september | tolerable weather |
| Glenariff in september | tolerable weather |
| Cookstown in september | tolerable weather |
Click over cities on the map for information about the weather in september.
Castlerock
perfect weather
good
tolerable
bad
very bad
Weather data for Castlerock in september:
Weather data for Castlerock for september are derived from an average of the weather forecast since 2009 in Castlerock. There is a margin of error and these forecasts are to be considered as general information only. The weather in Castlerock can vary slightly from year to year, but this data should limit surprises. So you can pack your bags or check for the best time in year to go to Castlerock.