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

TIDE TIMES for Thursday, July 30, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide : 11:00 am (0.6 ft)
Next high tide : in 3h 36m at 5:19 am (0.9 ft)
Sunset today : 8:09 pm
Sunrise tomorrow : 6:50 am
Moon phase : Full Moon (99% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Oct 1970

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Thu4:151.64:561.411:260.511:260.97:157:11New Moon1Thu
2Fri4:421.65:351.412:020.47:167:10Waxing Crescent2Fri
3Sat5:111.66:161.312:400.37:167:09Waxing Crescent3Sat
4Sun5:421.67:011.112:121.01:230.37:167:08Waxing Crescent4Sun
5Mon6:171.67:531.012:381.02:130.47:177:07Waxing Crescent5Mon
6Tue6:581.69:000.91:071.13:140.47:177:06First Quarter6Tue
7Wed7:521.610:300.91:441.14:270.57:187:05First Quarter7Wed
8Thu9:041.611:561.02:421.25:440.67:187:04First Quarter8Thu
9Fri10:351.64:241.26:530.67:187:03First Quarter9Fri
10Sat12:501.112:031.66:071.27:490.67:197:02Waxing Gibbous10Sat
11Sun1:281.21:151.77:281.08:350.77:197:01Waxing Gibbous11Sun
12Mon2:031.42:181.78:330.79:150.77:207:00Waxing Gibbous12Mon
13Tue2:371.53:141.79:300.59:520.87:206:59Full Moon13Tue
14Wed3:111.74:061.610:230.310:270.87:216:58Full Moon14Wed
15Thu3:471.84:561.511:120.111:020.87:216:57Full Moon15Thu
16Fri4:241.95:441.412:010.07:226:56Waning Gibbous16Fri
17Sat5:031.96:311.212:500.17:226:55Waning Gibbous17Sat
18Sun5:451.87:191.112:130.91:410.27:236:54Waning Gibbous18Sun
19Mon6:281.78:121.012:501.02:380.37:236:53Waning Gibbous19Mon
20Tue7:171.69:171.01:301.03:410.57:246:53Third Quarter20Tue
21Wed8:131.510:451.02:211.14:510.67:246:52Third Quarter21Wed
22Thu9:231.43:411.25:590.77:256:51Third Quarter22Thu
23Fri12:041.010:46 AM1.45:181.26:570.87:256:50Third Quarter23Fri
24Sat12:481.112:051.46:401.27:450.97:266:49Waning Crescent24Sat
25Sun1:181.212:071.46:441.17:230.96:265:48Waning Crescent25Sun
26Mon12:431.312:581.47:350.97:550.96:275:48Waning Crescent26Mon
27Tue1:071.41:421.48:180.78:240.96:275:47Waning Crescent27Tue
28Wed1:331.52:231.48:560.68:500.96:285:46New Moon28Wed
29Thu2:011.63:041.39:320.49:160.96:295:45New Moon29Thu
30Fri2:311.63:451.310:080.39:410.96:295:45New Moon30Fri
31Sat3:031.74:271.210:450.210:080.96:305:44New Moon31Sat
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 8:09 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 99% 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 Full Moon (99% 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