Measurements:
°C
°F
New Castle
26°F
SW 7 mph
Feels like: 16°F
Precip: 0%
World Resorts USA New Castle Weather

New Castle Sea Water Temperature

Current Sea Water Temperature:
+43.8°F
Maximum Sea Water Temperature in December: 51.0°F
Minimum Sea Water Temperature in December: 34.2°F
Average water temperature in December: 43.2°F

Sea Water Temperature for the Last 10 Days:

December 05 43.8°F November 30 46.8°F
December 04 46.0°F November 29 47.0°F
December 03 45.6°F November 28 48.4°F
December 02 45.8°F November 27 49.2°F
December 01 46.6°F November 26 48.2°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 43.3 °F
The most rainy months:
July 3 days
August 3 days
April 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 -2
Hawaii +78
Honolulu +78
Houston +44
Las Vegas +40
Los Angeles +52
Maui +72
Miami +72
Miami Beach +80
New York +18
San Diego +54
San Francisco +46
Sarasota +62
Tampa +62
Washington +28
24 Hours Weather Forecast
New Castle
Local time: 02:58
05 dec, friday
0300 26°F
SW
7 mph
0600 24°F
W
3 mph
0900 22°F
NW
6 mph
1200 26°F
NW
2 mph
1500 28°F
NW
2 mph
1800 28°F
S
2 mph
2100 26°F
SW
2 mph
06 dec, saturday
0000 28°F
S
2 mph