Dewey Beach Water Temperature
Sea-surface temperature at Dewey Beach, Delaware · times in EDT
Updated 4:00 AM EDT
How it compares today
Water temperature through the year
Monthly normals computed from 2023–2025 daily sea-surface temperature history.
Nearby water right now
7-day outlook
| Day | Air high / low | Max UV | Rain |
|---|---|---|---|
| Tue, Oct 13 | 74° / 57° | 5 | 4% |
| Wed, Oct 14 | 85° / 65° | 5 | 8% |
| Thu, Oct 15 | 70° / 61° | 5 | 21% |
| Fri, Oct 16 | 82° / 54° | 5 | 44% |
| Sat, Oct 17 | 55° / 47° | 5 | 17% |
| Sun, Oct 18 | 58° / 43° | 5 | 2% |
| Mon, Oct 19 | 64° / 46° | 4 | 2% |
Sea-surface temperature and wave data from the Open-Meteo marine model; weather from Open-Meteo.
Is Dewey Beach warm enough to swim?
At 66°F, the water at Dewey Beach is cool but swimmable. Most swimmers are comfortable without a wetsuit above 72°F; below 62°F, cold-water shock becomes a real risk for unprotected swimmers.
That is 1° below the October average of 67°F here.
The water averages above 70°F in July, August and September — 3 months of the year — peaking around 75°F in July and dropping to about 42°F in February.
Frequently asked questions
How warm is the water at Dewey Beach right now?
The sea-surface temperature is about 66°F. That is 1° below the October average of 67°F here.
When is the water warm enough to swim at Dewey Beach?
The water averages above 70°F in July, August and September — 3 months of the year — peaking around 75°F in July and dropping to about 42°F in February.
What is the warmest the water gets at Dewey Beach?
Around 75°F in July, based on 2023–2025 records. The coolest month is February at roughly 42°F.