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

TIDE TIMES for Sunday, June 21, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide : 4:32 pm (0.4 ft)
Next high tide : in 4h 59m at 9:37 am (1.0 ft)
Sunset today : 8:15 pm
Sunrise tomorrow : 6:35 am
Moon phase : First Quarter (48% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Aug 2017

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue11:171.25:420.67:180.36:518:08First Quarter1Tue
2Wed12:540.712:121.26:340.78:160.36:528:07Waxing Gibbous2Wed
3Thu1:590.71:031.37:260.79:070.26:528:06Waxing Gibbous3Thu
4Fri2:460.81:491.38:150.79:490.16:538:06Waxing Gibbous4Fri
5Sat3:240.82:331.49:000.710:260.16:538:05Waxing Gibbous5Sat
6Sun3:570.93:151.49:420.611:000.06:548:04Full Moon6Sun
7Mon4:300.93:561.510:210.611:320.06:548:04Full Moon7Mon
8Tue5:031.04:371.511:000.56:558:03Full Moon8Tue
9Wed5:371.15:191.512:050.011:40 AM0.56:558:02Full Moon9Wed
10Thu6:111.16:011.412:370.112:240.56:568:02Waning Gibbous10Thu
11Fri6:461.26:451.31:110.21:110.46:568:01Waning Gibbous11Fri
12Sat7:221.27:341.21:470.32:050.46:568:00Waning Gibbous12Sat
13Sun8:021.38:291.12:260.43:070.46:577:59Third Quarter13Sun
14Mon8:481.39:381.03:100.54:170.36:577:58Third Quarter14Mon
15Tue9:421.311:040.93:590.65:320.36:587:58Third Quarter15Tue
16Wed10:471.44:560.76:450.26:587:57Third Quarter16Wed
17Thu12:320.811:57 AM1.56:010.77:540.16:597:56Waning Crescent17Thu
18Fri1:430.91:041.57:070.78:540.06:597:55Waning Crescent18Fri
19Sat2:390.92:051.68:110.69:460.06:597:54Waning Crescent19Sat
20Sun3:261.03:001.79:100.510:320.07:007:53New Moon20Sun
21Mon4:081.13:521.710:040.411:140.07:007:52New Moon21Mon
22Tue4:461.24:411.610:560.411:540.17:017:51New Moon22Tue
23Wed5:241.25:271.611:460.37:017:51Waxing Crescent23Wed
24Thu6:001.36:111.512:330.212:350.47:017:50Waxing Crescent24Thu
25Fri6:351.36:541.31:110.41:260.47:027:49Waxing Crescent25Fri
26Sat7:111.47:371.21:490.52:190.57:027:48Waxing Crescent26Sat
27Sun7:491.48:241.12:290.63:170.57:037:47First Quarter27Sun
28Mon8:311.39:211.03:110.74:200.67:037:46First Quarter28Mon
29Tue9:201.310:400.93:580.85:280.67:037:45First Quarter29Tue
30Wed10:191.34:530.96:360.67:047:44First Quarter30Wed
31Thu12:170.911:25 AM1.35:541.07:390.57:047:43Waxing Gibbous31Thu
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 1:04 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.

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 neap phase. Tonight's moon is 48% 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 minimum.

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 First Quarter (48% illuminated). This places Grassy Key, north side, Florida Bay, FL in a neap tide cycle, so tidal ranges are near their weekly minimum 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