World Resorts USA Block Island Weather

Block Island Sea Temperature in September

Average sea water temperature in September:
+68.3°F
Minimum sea water temperature in September: 72.7°F
Maximum sea water temperature in September: 62.8°F

Daily sea water temperature in September, °F

Show year:
2025
2024
2023

The average sea water temperature in September of 2025 was 68.0°F. The highest and lowest sea temperatures during the month were 68.9°F and 66.6°F.

Monthly sea water temperature in Block Island, °F

Which USA resorts have warmest sea in September?

Place name September 2025 September 2024
Key West 86.9°F 87.4°F
Islamorada 86.7°F 87.3°F
Key Largo 86.6°F 87.1°F
Fort Lauderdale 86.4°F 86.4°F
West Palm Beach 86.2°F 86.4°F
Everglades 86.2°F 87.0°F
Miami Beach 86.1°F 86.3°F
Naples 86.1°F 87.2°F
Marco Island 86.0°F 87.2°F
South Padre Island 86.0°F 85.8°F
Corpus Christi 85.8°F 84.7°F
Miami 85.8°F 86.0°F
Sanibel Island 85.7°F 87.0°F
Galveston Island 85.5°F 84.4°F
Galveston 85.5°F 83.7°F
Cape Coral 85.2°F 86.5°F
Houston 84.9°F 83.4°F
Siesta Key 84.9°F 86.8°F
Sarasota 84.8°F 86.7°F
Cocoa Beach 84.6°F 85.2°F

Best time for vacation in Block Island

Sunniest months:
November 16 days
September 14 days
October 14 days
Warmest months:
July 74.4 °F
August 73.5 °F
September 68.8 °F
Warmest sea temp:
August 70.1 °F
July 68.6 °F
September 68.3 °F
Coldest months:
January 37.4 °F
February 37.4 °F
March 42.7 °F
Rainiest months:
October 4 days
January 3 days
March 3 days
Windiest months:
November 15.7 mph
January 15.6 mph
March 15.4 mph

Block Island on a weather map

Block Island
+41°F
N 14 mph
Feels like: +34°F
Precip.: 100%
Places in USA:
Name
°F
+50°F
+75°F
+75°F
+64°F
+59°F
+77°F
+79°F
+70°F
+37°F
+63°F
+57°F
+79°F
+77°F
+75°F
+41°F
24 Hours Forecast
Block Island
Local time: 19:10
December 23, tuesday
2100
41°F
E
18 mph
December 24, wednesday
0000
41°F
E
21 mph
0300
41°F
E
22 mph
0600
37°F
SE
22 mph
0900
37°F
SE
30 mph
1200
37°F
SE
30 mph
1500
41°F
S
24 mph
1800
41°F
S
17 mph
Units of measurement: °C / °F