Tides Today & Tomorrow in Grassy Key, north side, Florida Bay, FL

TIDE TIMES for Sunday, August 16, 2026
The tide is currently falling in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : in 5h 38m at 1:46 am (0.5 ft)
Next high tide (tomorrow) : 7:08 am (1.4 ft)
Sunset today : 7:57 pm
Sunrise tomorrow : 6:58 am
Moon phase : Waxing Crescent (18% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Jul 1939

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat4:410.73:511.410:130.411:35-0.36:378:16Full Moon1Sat
2Sun5:160.84:301.310:560.46:388:17Full Moon2Sun
3Mon5:490.85:081.312:12-0.211:38 AM0.46:388:17Full Moon3Mon
4Tue6:210.95:461.312:48-0.212:200.46:388:17Waning Gibbous4Tue
5Wed6:540.96:241.21:23-0.11:040.56:398:17Waning Gibbous5Wed
6Thu7:280.97:041.11:590.01:510.56:398:16Waning Gibbous6Thu
7Fri8:041.07:471.02:350.12:450.56:398:16Waning Gibbous7Fri
8Sat8:421.08:370.93:100.23:460.56:408:16Third Quarter8Sat
9Sun9:241.09:370.83:470.34:520.46:408:16Third Quarter9Sun
10Mon10:111.110:540.74:270.45:580.36:418:16Third Quarter10Mon
11Tue11:031.15:120.57:020.26:418:16Third Quarter11Tue
12Wed12:180.711:57 AM1.26:030.58:010.06:428:16Waning Crescent12Wed
13Thu1:310.712:511.36:580.58:54-0.16:428:16Waning Crescent13Thu
14Fri2:320.71:461.47:540.59:44-0.36:428:15Waning Crescent14Fri
15Sat3:230.72:391.58:500.410:30-0.46:438:15New Moon15Sat
16Sun4:090.83:321.69:440.311:15-0.46:438:15New Moon16Sun
17Mon4:530.94:251.610:370.311:58-0.46:448:15New Moon17Mon
18Tue5:361.05:171.511:310.26:448:14Waxing Crescent18Tue
19Wed6:181.06:101.512:42-0.312:270.26:458:14Waxing Crescent19Wed
20Thu7:011.17:031.31:26-0.21:270.26:458:14Waxing Crescent20Thu
21Fri7:451.28:001.22:100.02:310.26:468:13Waxing Crescent21Fri
22Sat8:331.29:021.02:560.13:420.26:468:13First Quarter22Sat
23Sun9:251.310:160.83:450.34:560.26:478:13First Quarter23Sun
24Mon10:241.311:440.74:360.46:110.26:478:12First Quarter24Mon
25Tue11:261.35:310.57:220.16:478:12Waxing Gibbous25Tue
26Wed1:070.712:281.36:290.58:250.16:488:11Waxing Gibbous26Wed
27Thu2:120.71:241.37:280.59:180.06:488:11Waxing Gibbous27Thu
28Fri3:020.72:131.48:230.510:020.06:498:10Waxing Gibbous28Fri
29Sat3:420.82:571.49:140.510:390.06:498:10Full Moon29Sat
30Sun4:160.83:371.410:010.511:130.06:508:09Full Moon30Sun
31Mon4:460.94:151.410:430.511:460.06:508:09Full Moon31Mon
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8723921)

Common Questions About Grassy Key, north side, Florida Bay, FL Tides

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What time does the tide turn (slack tide) in Grassy Key, north side, Florida Bay, FL today?

Slack tide in Grassy Key, north side, Florida Bay, FL is approximately 4:27 am — 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.

Is this week a spring tide or neap tide in Grassy Key, north side, Florida Bay, FL?

Grassy Key, north side, Florida Bay, FL is currently in a spring phase. Tonight's moon is 18% 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.

What datum are Grassy Key, north side, Florida Bay, FL tide heights measured from?

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.

What factors can affect the tide predictions for Grassy Key, north side, Florida Bay, FL?

Tide predictions for Grassy Key, north side, Florida Bay, 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.

Which NOAA station provides tide data for Grassy Key, north side, Florida Bay, FL?

Tide data for Grassy Key, north side, Florida Bay, FL is sourced from NOAA Station #8723921. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8723921.

What is the moon phase in Grassy Key, north side, Florida Bay, FL tonight?

Tonight the moon over Grassy Key, north side, Florida Bay, FL is Waxing Crescent (18% illuminated). This places Grassy Key, north side, Florida Bay, FL in a spring tide cycle, so tidal ranges are near their weekly maximum this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA