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

TIDE TIMES for Saturday, July 4, 2026
The tide is currently falling in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : in 4h 46m at 2:31 am (0.0 ft)
Next high tide (tomorrow) : 8:06 am (0.9 ft)
Sunset today : 8:17 pm
Sunrise tomorrow : 6:39 am
Moon phase : Waning Gibbous (81% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Sep 1999

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed7:481.58:431.12:140.63:130.47:047:42Third Quarter1Wed
2Thu8:381.59:581.03:000.74:250.47:057:41Third Quarter2Thu
3Fri9:391.511:280.93:540.85:410.47:057:40Third Quarter3Fri
4Sat10:531.54:580.96:550.37:057:39Waning Crescent4Sat
5Sun12:510.912:081.56:090.98:030.37:067:38Waning Crescent5Sun
6Mon1:531.01:171.67:200.89:000.37:067:37Waning Crescent6Mon
7Tue2:421.12:161.68:240.89:470.37:067:36Waning Crescent7Tue
8Wed3:231.23:091.79:210.610:290.37:077:35New Moon8Wed
9Thu4:001.33:571.710:120.611:060.47:077:34New Moon9Thu
10Fri4:341.34:411.611:000.511:420.47:077:33New Moon10Fri
11Sat5:061.45:221.611:450.57:087:32New Moon11Sat
12Sun5:381.56:011.512:160.512:300.57:087:31Waxing Crescent12Sun
13Mon6:101.56:401.412:510.61:150.57:097:30Waxing Crescent13Mon
14Tue6:421.57:201.21:250.72:020.57:097:29Waxing Crescent14Tue
15Wed7:171.58:041.11:590.82:540.67:097:28Waxing Crescent15Wed
16Thu7:571.48:581.02:351.03:530.67:107:27First Quarter16Thu
17Fri8:431.410:131.03:151.04:590.77:107:26First Quarter17Fri
18Sat9:421.411:491.04:091.16:080.77:107:25First Quarter18Sat
19Sun10:521.45:201.27:120.77:117:24First Quarter19Sun
20Mon1:021.012:021.46:321.28:060.67:117:22Waxing Gibbous20Mon
21Tue1:471.11:031.57:331.18:510.67:117:21Waxing Gibbous21Tue
22Wed2:221.11:561.68:251.09:290.57:127:20Waxing Gibbous22Wed
23Thu2:551.22:451.69:120.810:040.57:127:19Waxing Gibbous23Thu
24Fri3:281.33:321.79:560.710:370.57:127:18Full Moon24Fri
25Sat4:011.44:181.710:400.511:110.57:137:17Full Moon25Sat
26Sun4:351.55:051.611:250.411:450.67:137:16Full Moon26Sun
27Mon5:111.65:531.512:120.37:147:15Waning Gibbous27Mon
28Tue5:491.76:441.412:210.71:020.37:147:14Waning Gibbous28Tue
29Wed6:301.77:381.312:590.81:570.37:147:13Waning Gibbous29Wed
30Thu7:161.78:401.21:410.93:000.37:157:12Third Quarter30Thu
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 5:18 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 81% 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 Waning Gibbous (81% 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