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

TIDE TIMES for Sunday, June 21, 2026
The tide is currently falling in Grassy Key, north side, Florida Bay, FL.
Next low tide : in 36m at 4:05 am (0.1 ft)
Next high tide : 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 - Sep 2017

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Fri1:270.912:271.46:561.08:320.57:047:42Waxing Gibbous1Fri
2Sat2:120.91:221.47:520.99:160.47:057:41Waxing Gibbous2Sat
3Sun2:471.02:111.58:400.99:530.47:057:40Waxing Gibbous3Sun
4Mon3:191.12:561.59:240.810:260.47:067:39Full Moon4Mon
5Tue3:511.23:391.610:050.710:580.47:067:38Full Moon5Tue
6Wed4:231.34:221.610:460.611:290.47:067:37Full Moon6Wed
7Thu4:561.35:061.611:270.57:077:36Full Moon7Thu
8Fri5:301.45:501.512:020.412:110.47:077:35Waning Gibbous8Fri
9Sat6:051.56:371.412:350.512:590.47:077:34Waning Gibbous9Sat
10Sun6:431.57:271.31:110.61:520.37:087:32Waning Gibbous10Sun
11Mon7:241.58:251.21:500.72:520.47:087:31Third Quarter11Mon
12Tue8:131.59:361.12:350.84:010.47:087:30Third Quarter12Tue
13Wed9:131.511:031.03:280.95:160.47:097:29Third Quarter13Wed
14Thu10:281.54:351.06:310.47:097:28Third Quarter14Thu
15Fri12:271.011:48 AM1.65:501.07:390.47:097:27Waning Crescent15Fri
16Sat1:301.11:001.67:040.98:370.47:107:26Waning Crescent16Sat
17Sun2:191.22:021.78:110.89:260.47:107:25Waning Crescent17Sun
18Mon3:011.32:561.79:090.710:080.47:117:24New Moon18Mon
19Tue3:381.43:451.710:010.610:460.57:117:23New Moon19Tue
20Wed4:131.44:301.610:490.511:220.57:117:22New Moon20Wed
21Thu4:461.55:131.611:340.411:570.67:127:21New Moon21Thu
22Fri5:191.65:531.512:180.47:127:20Waxing Crescent22Fri
23Sat5:511.66:321.412:320.71:030.47:127:19Waxing Crescent23Sat
24Sun6:251.67:121.31:060.81:490.57:137:17Waxing Crescent24Sun
25Mon7:001.57:561.21:410.92:390.67:137:16Waxing Crescent25Mon
26Tue7:401.58:481.12:171.03:360.77:137:15First Quarter26Tue
27Wed8:261.49:581.02:591.14:410.77:147:14First Quarter27Wed
28Thu9:241.411:291.03:571.25:480.77:147:13First Quarter28Thu
29Fri10:341.45:121.26:530.77:157:12First Quarter29Fri
30Sat12:421.111:47 AM1.46:261.27:480.77:157:11Waxing Gibbous30Sat
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 6:51 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