Longboat Key water temp
This data the coastal Longboat Key ocean water temperature today, tomorrow and the upcoming days. Besides, you can also get information about the weather and surf forecast, as well as the data on sunrise / sunset and moonrise / moonset at a given point on any given day.
Current ocean temperature in Longboat Key
Water temperature in Longboat Key today is 85.5°F. Based on our historical data over a period of ten years, the warmest water in this day in Longboat Key was recorded in 2024 and was 86.9°F, and the coldest was recorded in 2008 at 84°F. Sea water temperature in Longboat Key is expected to drop to 84.9°F in the next 10 days. September average water temperature in Longboat Key is 85.3°F, the minimum temperature is 80.4°F, and the maximum is 88.2°F.
The swimming season in Longboat Key lasts from February to December. During those months, Longboat Key water temperature does not drop below 68°F and therefore suitable for comfortable swimming. The average water temperature in Longboat Key in winter reaches 66.4°F, in spring 74.5°F, in summer the average temperature rises to 85.8°F, and in autumn it is 79.9°F.
Longboat Key water temperature now
| September 11, 2025 |
|---|
| today temp |
| 85.5°F |
| September 10, 2025 |
|---|
| yesterday temp |
| 86°F |
The ocean salinity in Longboat Key is 36.45‰, and the average salinity of the World Ocean is 35‰.
Surf Forecast in Longboat Key for today
Another important indicators for a comfortable holiday on the beach are the presence and height of the waves, as well as the speed and direction of the wind. Please find below data on the swell size for Longboat Key. We calculate the swell size based on the mean wave height (trough to crest) of each third highest wave. For more information on surf forecasts for the next ten days, please visit sea state forecast Longboat Key. Data in table shown for September 11, 2025, time in GMT 0 format (you can change the time zone on the sea state forecast page)
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
| 1' 1" | 0' 11" | 0' 11" | 1' 0" |
| 0.34 m | 0.28 m | 0.27 m | 0.31 m |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| 1' 1" | 0' 9" | 0' 6" | 0' 7" |
| 0.32 m | 0.23 m | 0.15 m | 0.18 m |
Surf report in Longboat Key
Longboat Key weather forecast
Current temperature and weather
Data in a table show Longboat Key temperature today (September 11, 2025). For more information and forecast for a few days, go to the weather forecast Longboat Key.
| 0-3 h | 3-6 h | 6-9 h | 9-12 h |
|---|---|---|---|
 |  |  |  |
| 79.3°F | 77.7°F | 77°F | 76.5°F |
| 12-15 h | 15-18 h | 18-21 h | 21-24 h |
|---|---|---|---|
| | | |
| 80.8°F | 84.2°F | 83.7°F | 80.4°F |
You may also be interested in other sections of our site for Longboat Key: Sunrise and Sunset, Tides
Longboat Key water temperature by month
These figures shows the average, minimum and maximum monthly sea temperature in Longboat Key. In addition to the table values, the graph below displays of changes average surface temperature during the year. Values are calculated based on the data over the past 10 years. Using them, you can check the water temperature in Longboat Key on any day of this period that interests you. Click on the month link and you will see a table for each day, or alternatively you can view the temperature curve of the month and select 2 different years you want to compare, either in a table or as a curve
| Month | Avr | Min | Max | |
|---|---|---|---|---|
| January | 64.9°F | 55°F | 74.1°F | cold |
| Ocean water temperature in Longboat Key in January | ||||
| February | 65.7°F | 59.4°F | 75°F | cold |
| Ocean water temperature in Longboat Key in February | ||||
| March | 69.1°F | 58.3°F | 79°F | warm |
| Ocean water temperature in Longboat Key in March | ||||
| April | 74.5°F | 64.2°F | 80.6°F | warm |
| Ocean water temperature in Longboat Key in April | ||||
| May | 79.7°F | 73.6°F | 86.7°F | hot |
| Ocean water temperature in Longboat Key in May | ||||
| June | 84.2°F | 76.6°F | 88.2°F | hot |
| Ocean water temperature in Longboat Key in June | ||||
| July | 86.4°F | 83.5°F | 89.2°F | hot |
| Ocean water temperature in Longboat Key in July | ||||
| August | 86.7°F | 83.5°F | 91.4°F | hot |
| Ocean water temperature in Longboat Key in August | ||||
| September | 85.3°F | 80.4°F | 88.2°F | hot |
| Ocean water temperature in Longboat Key in September | ||||
| October | 80.6°F | 72.5°F | 86.7°F | hot |
| Ocean water temperature in Longboat Key in October | ||||
| November | 73.6°F | 67.1°F | 82.2°F | warm |
| Ocean water temperature in Longboat Key in November | ||||
| December | 68.5°F | 60.6°F | 74.1°F | warm |
| Ocean water temperature in Longboat Key in December | ||||
Chart monthly average water temperature in Longboat Key
