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 1h 44m 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 - Oct 2017

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun1:271.112:511.57:281.18:330.77:157:10Waxing Gibbous1Sun
2Mon2:031.21:451.58:201.09:110.77:167:09Waxing Gibbous2Mon
3Tue2:351.32:341.69:050.99:450.67:167:08Waxing Gibbous3Tue
4Wed3:071.43:211.69:480.710:180.67:177:07Full Moon4Wed
5Thu3:401.54:071.610:300.510:510.77:177:06Full Moon5Thu
6Fri4:151.64:531.611:130.411:250.77:177:05Full Moon6Fri
7Sat4:501.75:401.511:590.37:187:04Waning Gibbous7Sat
8Sun5:281.76:301.412:010.712:470.27:187:03Waning Gibbous8Sun
9Mon6:101.77:221.312:380.81:400.27:197:02Waning Gibbous9Mon
10Tue6:551.78:221.21:200.92:390.37:197:01Waning Gibbous10Tue
11Wed7:491.79:321.12:081.03:470.47:207:00Third Quarter11Wed
12Thu8:541.610:531.13:081.15:000.57:206:59Third Quarter12Thu
13Fri10:141.64:261.16:120.67:216:58Third Quarter13Fri
14Sat12:081.111:40 AM1.65:501.17:170.67:216:57Waning Crescent14Sat
15Sun1:061.212:541.67:061.08:110.67:216:56Waning Crescent15Sun
16Mon1:521.31:571.68:120.88:570.77:226:55Waning Crescent16Mon
17Tue2:311.42:501.69:080.79:370.77:226:55Waning Crescent17Tue
18Wed3:061.53:371.69:560.510:130.77:236:54New Moon18Wed
19Thu3:391.64:191.510:400.410:480.87:236:53New Moon19Thu
20Fri4:101.64:581.411:210.411:210.87:246:52New Moon20Fri
21Sat4:411.75:361.412:010.37:246:51New Moon21Sat
22Sun5:121.76:131.312:410.47:256:50Waxing Crescent22Sun
23Mon5:451.66:511.212:260.91:220.47:266:50Waxing Crescent23Mon
24Tue6:201.67:341.112:581.02:070.57:266:49Waxing Crescent24Tue
25Wed6:591.58:221.11:311.12:570.67:276:48Waxing Crescent25Wed
26Thu7:431.59:231.12:091.23:540.67:276:47First Quarter26Thu
27Fri8:371.410:351.13:031.24:560.77:286:46First Quarter27Fri
28Sat9:441.411:431.14:251.35:580.77:286:46First Quarter28Sat
29Sun11:021.45:501.26:530.77:296:45First Quarter29Sun
30Mon12:331.212:141.46:581.17:400.77:296:44Waxing Gibbous30Mon
31Tue1:131.31:171.47:540.98:210.77:306:44Waxing Gibbous31Tue
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