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

TIDE TIMES for Friday, July 31, 2026
The tide is currently falling in Grassy Key, north side, Florida Bay, FL.
Next low tide : in 3h 50m at 11:42 am (0.5 ft)
Next high tide : 5:20 pm (1.4 ft)
Sunset today : 8:08 pm
Sunrise tomorrow : 6:51 am
Moon phase : Waning Gibbous (96% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Sep 2091

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat6:081.36:241.412:480.51:030.57:057:42Waning Gibbous1Sat
2Sun6:391.47:031.31:200.61:470.57:057:41Waning Gibbous2Sun
3Mon7:131.47:441.11:520.72:350.67:057:40Waning Gibbous3Mon
4Tue7:501.48:331.02:240.83:300.67:067:39Third Quarter4Tue
5Wed8:321.39:361.02:590.94:330.67:067:38Third Quarter5Wed
6Thu9:251.311:000.93:411.05:420.67:067:37Third Quarter6Thu
7Fri10:291.34:401.06:480.67:077:36Third Quarter7Fri
8Sat12:240.911:39 AM1.45:501.07:470.57:077:35Waning Crescent8Sat
9Sun1:251.012:441.56:581.08:370.47:077:34Waning Crescent9Sun
10Mon2:101.11:411.67:590.99:200.47:087:32Waning Crescent10Mon
11Tue2:501.22:351.68:530.810:000.37:087:31Waning Crescent11Tue
12Wed3:271.33:251.79:440.610:380.37:097:30New Moon12Wed
13Thu4:041.44:151.710:330.411:160.47:097:29New Moon13Thu
14Fri4:421.55:051.711:220.311:540.47:097:28New Moon14Fri
15Sat5:211.65:551.612:120.27:107:27Waxing Crescent15Sat
16Sun6:011.66:471.512:330.51:050.27:107:26Waxing Crescent16Sun
17Mon6:451.77:421.31:130.62:030.27:107:25Waxing Crescent17Mon
18Tue7:331.78:441.21:570.83:070.37:117:24First Quarter18Tue
19Wed8:281.610:001.12:480.94:180.47:117:23First Quarter19Wed
20Thu9:341.611:281.03:481.05:330.57:117:22First Quarter20Thu
21Fri10:511.55:011.06:460.57:127:21First Quarter21Fri
22Sat12:451.112:091.56:171.07:510.67:127:20Waxing Gibbous22Sat
23Sun1:421.11:161.67:271.08:430.67:127:19Waxing Gibbous23Sun
24Mon2:251.22:111.68:280.99:260.67:137:17Waxing Gibbous24Mon
25Tue3:011.32:581.69:200.810:020.67:137:16Full Moon25Tue
26Wed3:321.43:401.610:050.710:360.67:147:15Full Moon26Wed
27Thu4:001.44:181.610:460.611:070.77:147:14Full Moon27Thu
28Fri4:281.54:531.511:250.611:380.77:147:13Full Moon28Fri
29Sat4:561.55:291.512:020.57:157:12Full Moon29Sat
30Sun5:251.66:051.412:080.812:400.57:157:11Waning Gibbous30Sun
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 2:31 pm — 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 96% 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 (96% 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