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

TIDE TIMES for Friday, July 31, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : 12:47 am (0.1 ft)
Next high tide : in 1h 23m at 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 - Jan 1967

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sun6:161.37:280.812:320.31:56-0.17:085:46Waning Gibbous1Sun
2Mon7:161.18:130.91:410.32:430.07:085:46Third Quarter2Mon
3Tue8:261.09:031.03:000.23:310.27:085:47Third Quarter3Tue
4Wed9:520.89:571.14:210.14:200.37:095:48Third Quarter4Wed
5Thu11:250.710:541.25:390.05:110.47:095:48Waning Crescent5Thu
6Fri12:460.66:50-0.26:040.47:095:49Waning Crescent6Fri
7Sat1:520.67:54-0.46:570.47:095:50Waning Crescent7Sat
8Sun12:441.32:440.68:49-0.57:490.37:095:50Waning Crescent8Sun
9Mon1:351.33:280.69:37-0.68:390.37:095:51New Moon9Mon
10Tue2:241.34:070.610:20-0.69:270.27:105:52New Moon10Tue
11Wed3:101.34:410.611:00-0.510:120.27:105:53New Moon11Wed
12Thu3:531.35:130.611:38-0.410:570.27:105:53Waxing Crescent12Thu
13Fri4:341.25:440.712:16-0.37:105:54Waxing Crescent13Fri
14Sat5:141.26:140.712:52-0.27:105:55Waxing Crescent14Sat
15Sun5:531.16:450.812:300.21:29-0.17:105:56Waxing Crescent15Sun
16Mon6:350.97:180.81:230.32:040.17:105:56Waxing Crescent16Mon
17Tue7:210.87:540.82:230.32:390.27:105:57First Quarter17Tue
18Wed8:170.78:360.93:290.23:140.37:105:58First Quarter18Wed
19Thu9:330.59:240.94:380.13:520.47:095:59First Quarter19Thu
20Fri11:110.510:180.95:460.04:360.47:095:59First Quarter20Fri
21Sat12:390.46:50-0.25:280.57:096:00Waxing Gibbous21Sat
22Sun1:410.47:46-0.36:240.47:096:01Waxing Gibbous22Sun
23Mon12:131.12:270.58:36-0.57:190.47:096:02Waxing Gibbous23Mon
24Tue1:071.23:060.59:20-0.68:120.37:086:02Full Moon24Tue
25Wed1:591.33:420.610:02-0.79:020.27:086:03Full Moon25Wed
26Thu2:491.34:180.610:42-0.79:510.17:086:04Full Moon26Thu
27Fri3:391.44:530.711:21-0.610:420.07:086:05Full Moon27Fri
28Sat4:291.45:280.812:00-0.57:076:05Waning Gibbous28Sat
29Sun5:201.36:050.912:39-0.37:076:06Waning Gibbous29Sun
30Mon6:121.16:430.912:33-0.11:19-0.27:066:07Waning Gibbous30Mon
31Tue7:090.97:241.01:37-0.21:590.07:066:07Third Quarter31Tue
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 9:03 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