Measurements:
°C
°F
New Castle
76°F
SE 6 mph
Feels like: 80°F
Precip: 5%
World Resorts USA New Castle Weather

New Castle Sea Water Temperature

Current Sea Water Temperature:
+83.6°F
Maximum Sea Water Temperature in August: 90.2°F
Minimum Sea Water Temperature in August: 77.8°F
Average water temperature in August: 83.4°F

Sea Water Temperature for the Last 10 Days:

August 25 83.6°F August 20 84.8°F
August 24 84.0°F August 19 83.6°F
August 23 84.2°F August 18 85.6°F
August 22 84.8°F August 17 85.8°F
August 21 83.8°F August 16 86.0°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: 2026 2025 2024

The average sea surface temperature in July 2026 for New Castle was 83.4°F. The maximum and minimum values were 79.0°F and 85.6°F respectively.

Sea Water Temperature in August

Select Year: 2026 2025 2024

The average sea surface temperature in August 2026 for New Castle was 84.3°F. The maximum and minimum values were 82.6°F and 86.2°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
June 15 days
The most warm months:
July 89.9 °F
August 86.0 °F
June 83.9 °F
Warmest sea temperature:
July 84.1 °F
August 83.4 °F
September 77.2 °F
The most cold months:
January 37.3 °F
February 40.7 °F
December 42.3 °F
The most rainy months:
July 3 days
August 3 days
June 2 days
The most windy months:
March 9 mph
April 9 mph
January 8 mph

New Castle on the Weather Map

USA Resorts:
NAME
Boston +80
Chicago +80
Hawaii +84
Houston +106
Las Vegas +116
Los Angeles +96
Maui +70
Miami +92
Myrtle Beach +84
New York +82
San Diego +96
San Francisco +64
Santa Monica +86
Sarasota +92
Washington +84
24 Hours Weather Forecast
New Castle
Local time: 17:43
25 aug, tuesday
1800 76°F
SE
6 mph
2100 72°F
E
5 mph
26 aug, wednesday
0000 70°F
SE
4 mph
0300 68°F
S
5 mph
0600 66°F
S
3 mph
0900 74°F
S
2 mph
1200 82°F
N
4 mph
1500 86°F
N
7 mph