Big Coppitt Key — Water Temperature, Sea Conditions & Trends
This page provides clear and up-to-date information about water temperature for Big Coppitt Key (Florida, United States). It includes the current water temperature, daily data for the last month presented in a simple chart, and a 7-day forecast. The page also compares today’s value with typical averages for this period, shows usual monthly ranges during the year, and lists nearby beaches with short descriptions. Local weather for the next few days and general details about Big Coppitt Key help you plan your visit and choose the best time for swimming.
Current Water Temperature
Water temperature in Big Coppitt Key in the Gulf of America today is 29°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
✅ As of today, the minimum water temperature is above 82°F (28°C). This is very warm water, which may feel almost hot to most people. Swimming in such conditions is perfect for those seeking relaxation and comfort in the water. These waters are often preferred for relaxation in hot weather, as the water temperature does not cool the body significantly. However, it is important to remember that in such warm waters, caution is necessary, as prolonged exposure without rest can lead to overheating.
It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Water temperature in Big Coppitt Key today is lower than both a week ago and a month ago. Currently, the sea water temperature at this location matches the average for this day in previous years.
According to our forecast, Water temperature in Big Coppitt Key will be 28.6°C in the next 7 days. See the table below for daily data for the upcoming week.
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| JUN 4 | 30.1°C | 28.8°C | |
| JUN 5 | 30.0°C | 28.8°C | |
| JUN 6 | 30.0°C | 28.3°C | |
| JUN 7 | 29.4°C | 28.3°C | |
| JUN 8 | 29.4°C | 28.5°C | |
| JUN 9 | 29.0°C | 28.8°C | |
| JUN 10 | 28.8°C | 28.3°C | |
| JUN 11 | 28.8°C | 28.8°C | |
| JUN 12 | 28.9°C | 28.8°C | 28.9°C |
| JUN 13 | 29.0°C | 28.9°C | |
| JUN 14 | 28.8°C | 28.8°C | |
| JUN 15 | 28.5°C | 28.8°C | |
| JUN 16 | 28.5°C | 28.7°C | |
| JUN 17 | 28.5°C | 28.7°C | |
| JUN 18 | 28.5°C | 28.7°C | |
| JUN 19 | 28.3°C | 28.6°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Water temperature data for this location is gathered from various sources, including buoys and satellite sea and ocean surface maps provided by the NOAA agency. We also incorporate data from local authorities in each specific location worldwide to ensure more accurate temperature readings.
Annual Water Temperature Overview by Month
Monthly Water Temp Ranges
Annual Water Temperature Trend
Big Coppitt Key sits just east of Key West in the lower Florida Keys and is characterized by shallow bays, mangrove shorelines and residential waterfront access rather than long public sand beaches. Sea temperatures around the island are mild to warm for most of the year. Typical seasonal surface water values are approximately 21–24°C in winter (December–February), rising to about 23–26°C in spring (March–May). Summer months (June–August) usually see the warmest water, roughly 27–31°C, while autumn (September–November) typically ranges from about 25–29°C. Short-lived cold fronts can push temperatures down a few degrees in winter, while late summer brings the highest and most consistently warm readings.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 19°C | 22°C | 26°C |
| February | 19°C | 23°C | 26°C |
| March | 20°C | 24°C | 27°C |
| April | 22°C | 26°C | 28°C |
| May | 24°C | 27°C | 32°C |
| June | 26°C | 29°C | 31°C |
| July | 28°C | 30°C | 34°C |
| August | 28°C | 31°C | 33°C |
| September | 27°C | 30°C | 33°C |
| October | 25°C | 29°C | 31°C |
| November | 22°C | 26°C | 29°C |
| December | 21°C | 24°C | 27°C |
* Click on a month to view detailed water temperature data.
Big Coppitt Key: Weather Forecast
June 13
June 14
June 15
Location, Beaches & Local Information
Nearby Beaches & Facilities
Geiger Beach
Boca Chica Beach
Swimming Conditions
Swimming around Big Coppitt Key is generally pleasant for much of the year thanks to these warm waters, but the island’s shoreline is often rocky or mangrove-lined rather than broad sand, so many visitors choose to swim from small local spots, docks or by boat. For traditional beach-style sunbathing and easy shore entry, nearby Key West offers more extensive sandy beaches and swimming areas with similar warm water. Snorkeling and shallow-water exploration are popular, given good visibility and access to reefs and seagrass flats, though swimmers should be mindful of currents, boat traffic and occasional marine life like jellyfish. In cooler months a light wetsuit or shorty can improve comfort, while in summer simple swimwear is usually sufficient.