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

TIDE TIMES for Friday, July 17, 2026
The tide is currently falling in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : in 4h 02m at 1:55 am (0.0 ft)
Next high tide (tomorrow) : 7:21 am (1.0 ft)
Sunset today : 8:15 pm
Sunrise tomorrow : 6:44 am
Moon phase : Waxing Crescent (14% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Sep 2077

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed3:341.03:011.79:120.710:390.17:057:41Full Moon1Wed
2Thu4:091.13:551.810:070.611:180.27:057:40Full Moon2Thu
3Fri4:441.34:471.811:010.411:560.37:057:39Full Moon3Fri
4Sat5:201.45:391.711:540.37:067:38Waning Gibbous4Sat
5Sun5:561.56:311.612:330.412:490.27:067:37Waning Gibbous5Sun
6Mon6:351.67:251.41:100.61:480.27:077:36Waning Gibbous6Mon
7Tue7:161.68:241.21:490.72:510.27:077:35Third Quarter7Tue
8Wed8:031.69:351.02:300.84:010.37:077:34Third Quarter8Wed
9Thu8:591.611:090.93:170.95:180.47:087:33Third Quarter9Thu
10Fri10:081.54:151.06:360.47:087:32Third Quarter10Fri
11Sat12:460.911:28 AM1.55:271.17:500.47:087:31Waning Crescent11Sat
12Sun1:510.912:431.56:431.08:490.47:097:30Waning Crescent12Sun
13Mon2:351.01:441.57:521.09:340.57:097:29Waning Crescent13Mon
14Tue3:091.12:341.68:500.910:090.57:097:28Waning Crescent14Tue
15Wed3:371.23:171.69:390.810:400.57:107:27New Moon15Wed
16Thu4:021.33:551.610:220.711:080.67:107:26New Moon16Thu
17Fri4:251.34:301.611:010.711:360.67:107:25New Moon17Fri
18Sat4:501.45:051.511:380.67:117:23New Moon18Sat
19Sun5:161.55:411.512:020.712:140.67:117:22Waxing Crescent19Sun
20Mon5:431.56:181.412:270.812:520.57:127:21Waxing Crescent20Mon
21Tue6:121.56:581.312:510.91:320.57:127:20Waxing Crescent21Tue
22Wed6:421.57:431.11:140.92:170.57:127:19Waxing Crescent22Wed
23Thu7:161.58:391.01:371.03:120.57:137:18First Quarter23Thu
24Fri7:581.59:580.92:051.14:180.67:137:17First Quarter24Fri
25Sat8:531.511:430.92:441.25:330.67:137:16First Quarter25Sat
26Sun10:101.53:531.26:460.57:147:15First Quarter26Sun
27Mon12:591.011:35 AM1.65:331.27:490.57:147:14Waxing Gibbous27Mon
28Tue1:441.112:501.66:591.18:410.57:147:13Waxing Gibbous28Tue
29Wed2:211.21:541.78:091.09:250.57:157:12Waxing Gibbous29Wed
30Thu2:541.32:521.89:080.710:050.57:157:11Full Moon30Thu
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 4:38 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 spring phase. Tonight's moon is 14% 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 maximum.

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 Crescent (14% illuminated). This places Grassy Key, north side, Florida Bay, FL in a spring tide cycle, so tidal ranges are near their weekly maximum 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