Measurements:
°C
°F
New Castle
64°F
SW 6 mph
Feels like: 64°F
Precip: 4%
World Resorts USA New Castle Weather

New Castle Sea Water Temperature

Current Sea Water Temperature:
+81.2°F
Maximum Sea Water Temperature in September: 85.2°F
Minimum Sea Water Temperature in September: 71.0°F
Average water temperature in September: 77.6°F

Sea Water Temperature for the Last 10 Days:

September 15 81.2°F September 10 82.4°F
September 14 78.6°F September 09 81.6°F
September 13 81.0°F September 08 81.6°F
September 12 81.4°F September 07 81.4°F
September 11 81.8°F September 06 81.6°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 83.9°F. The maximum and minimum values were 82.0°F and 86.2°F respectively.

Sea Water Temperature in September

Select Year: 2026 2025 2024

The average sea surface temperature in September 2026 for New Castle was 81.5°F. The maximum and minimum values were 78.6°F and 83.2°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 86.4 °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 +62
Chicago +66
Hawaii +80
Las Vegas +80
Los Angeles +72
Maui +66
Miami +88
Myrtle Beach +78
New York +66
Panama City Beach +90
San Diego +70
San Francisco +60
Santa Monica +72
Sarasota +86
Washington +66
24 Hours Weather Forecast
New Castle
Local time: 09:41
15 sep, tuesday
1200 74°F
NW
6 mph
1500 80°F
N
4 mph
1800 74°F
N
7 mph
2100 64°F
NW
6 mph
16 sep, wednesday
0000 62°F
NW
4 mph
0300 60°F
NW
2 mph
0600 60°F
NW
1 mph
0900 68°F
N
4 mph