Tides Today & Tomorrow in Mayport Naval Station, St Johns R, FL

The lowest tide this week in Mayport Naval Station, St Johns R, FL is -1.1 ft on Wednesday, Jul 15 at 3:35 pm.

The highest tide this week in Mayport Naval Station, St Johns R, FL is 5.7 ft on Wednesday, Jul 15 at 10:19 pm — worth noting for launching your boat and being alert for possible high tide flooding.

Slack tide in Mayport Naval Station, St Johns R, FL is approximately 12:44 pm — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Mayport Naval Station, St Johns R, FL is currently in a spring phase. Tonight's moon is 2% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are near their weekly maximum.

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

Tide predictions for Mayport Naval Station, St Johns R, FL come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Tide data for Mayport Naval Station, St Johns R, FL is sourced from NOAA Station #8720211. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8720211.

High tides in Mayport Naval Station, St Johns R, FL today: 9:54 am (4.7 ft), 10:19 pm (5.7 ft). The 10:19 pm high of 5.7 ft is notably higher than the other — known as diurnal inequality, common on coasts influenced by lunar declination.

Low tides in Mayport Naval Station, St Johns R, FL today: 3:32 am (-0.8 ft), 3:35 pm (-1.1 ft). The 3:32 am low of -0.8 ft is a minus tide — water below the MLLW reference datum, which can expose tidepools, mudflats, and shellfish beds not normally accessible.

Today's tidal range in Mayport Naval Station, St Johns R, FL is 6.8 ft — the difference between the day's highest and lowest water level. This month's average daily range is about 5.1 ft, so today's swing is above-average.

Tonight the moon over Mayport Naval Station, St Johns R, FL is New Moon (2% illuminated). This places Mayport Naval Station, St Johns R, FL in a spring tide cycle, so tidal ranges are near their weekly maximum this week.

Mayport Naval Station, St Johns R, FL has semi-diurnal tides — two high tides and two low tides roughly every 24 hours and 50 minutes, with similar heights.