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

TIDE TIMES for Saturday, August 22, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : 6:39 am (1.0 ft)
Next high tide (tomorrow) : in 5h 36m at 2:29 am (0.7 ft)
Sunset today : 7:52 pm
Sunrise tomorrow : 7:01 am
Moon phase : Waxing Gibbous (73% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Jan 1929

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue7:171.18:160.91:450.32:510.17:085:46Third Quarter1Tue
2Wed8:210.99:050.93:040.33:380.27:085:47Third Quarter2Wed
3Thu9:380.89:561.04:220.34:260.47:095:47Third Quarter3Thu
4Fri11:080.710:461.05:350.25:130.47:095:48Third Quarter4Fri
5Sat12:280.66:420.16:000.57:095:49Waning Crescent5Sat
6Sun1:300.67:39-0.16:470.57:095:49Waning Crescent6Sun
7Mon12:181.12:180.68:27-0.27:310.47:095:50Waning Crescent7Mon
8Tue1:001.12:560.69:09-0.38:130.47:095:51Waning Crescent8Tue
9Wed1:411.23:290.69:47-0.48:510.47:105:51New Moon9Wed
10Thu2:211.24:010.610:22-0.49:270.37:105:52New Moon10Thu
11Fri3:011.24:330.610:56-0.410:020.37:105:53New Moon11Fri
12Sat3:411.25:050.711:30-0.410:390.37:105:54New Moon12Sat
13Sun4:211.25:380.712:04-0.47:105:54Waxing Crescent13Sun
14Mon5:011.26:110.712:39-0.37:105:55Waxing Crescent14Mon
15Tue5:431.16:450.812:050.21:14-0.27:105:56Waxing Crescent15Tue
16Wed6:301.07:200.812:580.21:510.07:105:57Waxing Crescent16Wed
17Thu7:240.97:590.92:020.22:310.17:105:57First Quarter17Thu
18Fri8:320.78:451.03:150.13:150.27:105:58First Quarter18Fri
19Sat10:020.69:401.04:31-0.14:030.37:095:59First Quarter19Sat
20Sun11:400.510:431.15:47-0.34:590.37:096:00Waxing Gibbous20Sun
21Mon1:010.56:59-0.45:590.37:096:00Waxing Gibbous21Mon
22Tue2:030.58:03-0.67:010.37:096:01Waxing Gibbous22Tue
23Wed12:511.32:520.59:00-0.78:000.27:096:02Full Moon23Wed
24Thu1:511.33:350.69:50-0.88:560.17:086:03Full Moon24Thu
25Fri2:461.44:140.610:37-0.79:500.07:086:03Full Moon25Fri
26Sat3:391.44:510.711:20-0.610:43-0.17:086:04Full Moon26Sat
27Sun4:291.35:270.812:01-0.57:086:05Waning Gibbous27Sun
28Mon5:171.26:020.812:40-0.37:076:05Waning Gibbous28Mon
29Tue6:041.16:380.912:31-0.11:19-0.17:076:06Waning Gibbous29Tue
30Wed6:520.97:140.91:300.01:580.07:076:07Third Quarter30Wed
31Thu7:430.77:540.92:330.02:370.27:066:08Third Quarter31Thu
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 4:34 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 transitional phase. Tonight's moon is 73% 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 shifting between spring and neap.

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 Gibbous (73% illuminated). This places Grassy Key, north side, Florida Bay, FL in a transitional tide cycle, so tidal ranges are shifting between spring and neap 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