Measurements:
°C
°F
New Castle
54°F
E 4 mph
Feels like: 54°F
Precip: 0%
World Resorts USA New Castle Weather

New Castle Sea Water Temperature

Current Sea Water Temperature:
+35.0°F
Maximum Sea Water Temperature in January: 43.2°F
Minimum Sea Water Temperature in January: 29.8°F
Average water temperature in January: 36.8°F

Sea Water Temperature for the Last 10 Days:

January 08 35.0°F January 03 35.8°F
January 07 33.6°F January 02 35.8°F
January 06 33.6°F January 01 36.2°F
January 05 35.2°F December 31 36.8°F
January 04 35.6°F December 30 36.4°F

When is the Warmest Sea for New Castle?

According to our data for the last three years for New Castle the highest average sea water temperature was in July, August and September.

Average Water Temperature by Month, °F

Sea Water Temperature in July

Select Year: 2025 2024 2023

The average sea surface temperature in July 2025 for New Castle was 84.6°F. The maximum and minimum values were 81.6°F and 87.4°F respectively.

Sea Water Temperature in August

Select Year: 2025 2024 2023

The average sea surface temperature in August 2025 for New Castle was 82.9°F. The maximum and minimum values were 78.8°F and 87.8°F respectively.

Sea Water Temperature in September

Select Year: 2025 2024 2023

The average sea surface temperature in September 2025 for New Castle was 76.2°F. The maximum and minimum values were 74.0°F and 78.6°F respectively.

Best Time to Visit New Castle
The most sunny months:
November 17 days
October 16 days
September 15 days
The most warm months:
July 89.5 °F
August 86.0 °F
June 83.1 °F
Warmest sea temperature:
July 84.2 °F
August 83.3 °F
September 77.2 °F
The most cold months:
January 37.9 °F
February 41.5 °F
December 42.3 °F
The most rainy months:
July 3 days
April 3 days
August 3 days
The most windy months:
March 9 mph
April 9 mph
January 8 mph

New Castle on the Weather Map

USA Resorts:
NAME
Chicago +54
Hawaii +78
Honolulu +78
Houston +78
Las Vegas +54
Los Angeles +58
Maui +72
Miami +86
Miami Beach +80
New York +52
San Diego +64
San Francisco +52
Sarasota +82
Tampa +88
Washington +60
24 Hours Weather Forecast
New Castle
Local time: 15:29
08 jan, thursday
1800 50°F
NE
2 mph
2100 34°F
N
3 mph
09 jan, friday
0000 30°F
N
4 mph
0300 28°F
N
4 mph
0600 30°F
N
6 mph
0900 32°F
N
7 mph
1200 34°F
N
9 mph
1500 38°F
N
9 mph