Normal weather for Castlerock in September
It's cool to moderate in September in Castlerock with an average temperature of 16°C. Temperatures this month range from a low of 15°C to a high of 19°C. At night, you can expect temperatures between 9°C and 13°C.
In September, there is an average of 76 mm of precipitation, spread over 10 days. The wind speed is around 4 Bft, mostly coming from the Southwest.
The water temperature at Castlerock is 14°C this month. This is too cold to swim without protective gear.
Looking for sun and warm weather? September isn’t a good month to be in Castlerock. The temperatures are too low for a warm stay this month.
Castlerock in September |
New York | ||
|---|---|---|---|
 Average Temperature |
16°C | 27°C | |
 High Temp |
19°C | 31°C | |
| Low Temp |
15°C | 21°C | |
 Total Precipitation |
76 mm | 57 mm | |
| Rainy Days |
10 days | 9 days | |
The UV index is a maximum of 4 this month. That's a moderate value on the intensity scale of 1 to 11. Unprotected skin can burn in about 30 minutes.
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Start of September
The month of September starts in Castlerock with mild temps, averaging around 18°C during the day and nights around 13°C. A few showers might pop up early in the month, but overall, it’ll stay mostly sunny and dry.
Mid September
By mid-September, daytime temps drop to around 17°C, with nights around 11°C. There’s a chance of some showers during this time, but plenty of dry and sunny days too.
End of September
By the end of September, the average daytime temperature in Castlerock is around 16°C, while nighttime temps are about 10°C. A shower might pop up, but overall, the weather will be dry and sunny.
Temperature records
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Daily Temperature in September in Castlerock
This chart shows the average daily high and low temperatures in September for Castlerock, in degrees Celsius. The red line represents the highs, and the blue line shows the lows. The days of the month are displayed at the bottom of the chart. The data, based on historical observations, provide the average temperatures for this month.
Daily Precipitation in September in Castlerock
The chart below shows the average daily precipitation in September for Castlerock, measured in millimeters over the past few years. Precipitation is always measured as water, even if it’s snow or hail. The days of the month are listed at the bottom of the chart.
A low average precipitation means that the chance of rain on that day is usually small, while a higher average suggests that it rained more often. But remember, it’s just an average, and every day can be different. Based on historical weather data for September, you can expect about 10 days of precipitation in Castlerock.
Daily UV Index in September in Castlerock
This chart shows the average daily UV index in September in Castlerock, with the UV index ranging from 0 to a maximum of 11. The bottom of the chart shows the days of the month. Based on historical data, this chart provides an idea of the daily UV radiation levels you can expect.
Temperature in September in Castlerock Over the Years
This chart shows the average temperature in September in Castlerock, measured in degrees Celsius, over the past few years.
Total Precipitation in September in Castlerock Over the Years
This chart shows the average precipitation in September in Castlerock, measured in millimeters over the past years. Precipitation is always measured as water, whether it’s snow or hail.
Daily Climate in September for Castlerock
Click on any day in September to get detailed info about the usual weather on that day in Castlerock. Check out the historical temperatures and precipitation over the past 10 years on this day.
Weather experiences in September in Castlerock
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Average Weather in Castlerock by Month
Click on a month below to see detailed weather info for Castlerock. Based on historical weather data, you can see the average temperature, precipitation, wind, and UV index for each day of the month.
Or check out the climate of Castlerock for all months at once
