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
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
Tampa 84.3°F 86.0°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
December 42.6 °F
Rainiest months:
October 4 days
January 3 days
March 3 days
Windiest months:
December 16.1 mph
November 15.7 mph
January 15.6 mph

Block Island on a weather map

Block Island
+27°F
E 36 mph
Feels like: +10°F
Precip.: 0%
Places in USA:
Name
°F
+37°F
+75°F
+75°F
+63°F
+64°F
+73°F
+75°F
+70°F
+30°F
+79°F
+52°F
+64°F
+59°F
+55°F
+19°F
24 Hours Forecast
Block Island
Local time: 15:42
December 30, tuesday
1800
30°F
E
37 mph
2100
32°F
E
34 mph
December 31, wednesday
0000
32°F
E
32 mph
0300
32°F
E
28 mph
0600
32°F
E
24 mph
0900
32°F
E
23 mph
1200
32°F
E
24 mph
1500
34°F
E
25 mph
Units of measurement: °C / °F