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 (tomorrow) : 4:50 am (0.3 ft)
Next high tide : in 4h 23m at 9:45 pm (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 - Sep 2016

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu4:221.24:201.610:410.511:270.47:057:42New Moon1Thu
2Fri4:531.34:591.511:240.57:057:41New Moon2Fri
3Sat5:241.45:361.512:010.412:060.57:057:40Waxing Crescent3Sat
4Sun5:541.46:121.412:340.512:480.57:067:39Waxing Crescent4Sun
5Mon6:251.46:501.31:070.61:310.57:067:37Waxing Crescent5Mon
6Tue6:591.47:301.21:390.72:180.67:067:36Waxing Crescent6Tue
7Wed7:351.48:151.12:110.83:100.67:077:35First Quarter7Wed
8Thu8:171.49:131.02:450.94:100.77:077:34First Quarter8Thu
9Fri9:071.310:310.93:261.05:170.77:077:33First Quarter9Fri
10Sat10:091.44:221.16:250.67:087:32First Quarter10Sat
11Sun12:000.911:18 AM1.45:341.17:260.67:087:31Waxing Gibbous11Sun
12Mon1:061.012:251.46:441.18:180.57:087:30Waxing Gibbous12Mon
13Tue1:531.11:241.57:451.09:020.57:097:29Waxing Gibbous13Tue
14Wed2:331.22:171.68:390.89:420.47:097:28Waxing Gibbous14Wed
15Thu3:091.33:081.79:290.710:190.47:107:27Full Moon15Thu
16Fri3:461.43:571.710:170.510:560.47:107:26Full Moon16Fri
17Sat4:221.54:461.711:050.411:330.57:107:25Full Moon17Sat
18Sun5:001.65:361.611:530.37:117:24Waning Gibbous18Sun
19Mon5:401.66:261.512:110.512:450.27:117:23Waning Gibbous19Mon
20Tue6:221.77:191.412:510.61:400.27:117:22Waning Gibbous20Tue
21Wed7:081.78:181.21:340.72:410.37:127:20Waning Gibbous21Wed
22Thu8:011.79:271.12:210.83:490.47:127:19Third Quarter22Thu
23Fri9:031.610:501.13:181.05:030.57:127:18Third Quarter23Fri
24Sat10:191.64:281.06:170.57:137:17Third Quarter24Sat
25Sun12:121.111:40 AM1.55:461.07:250.67:137:16Waning Crescent25Sun
26Mon1:141.112:531.67:001.08:210.67:147:15Waning Crescent26Mon
27Tue2:021.21:531.68:050.99:070.67:147:14Waning Crescent27Tue
28Wed2:411.32:431.69:010.89:460.67:147:13Waning Crescent28Wed
29Thu3:151.43:271.69:480.710:210.77:157:12New Moon29Thu
30Fri3:451.54:061.610:310.610:530.77:157:11New Moon30Fri
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 1:17 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 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