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

TIDE TIMES for Tuesday, July 21, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : 4:36 am (0.6 ft)
Next high tide : in 3h 04m at 10:22 pm (0.7 ft)
Sunset today : 8:13 pm
Sunrise tomorrow : 6:46 am
Moon phase : First Quarter (52% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Aug 2079

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Tue7:161.17:211.31:530.11:520.46:528:08Waxing Crescent1Tue
2Wed7:521.28:101.12:310.32:550.46:528:07First Quarter2Wed
3Thu8:301.29:050.93:090.54:010.46:538:07First Quarter3Thu
4Fri9:121.210:160.83:480.65:100.46:538:06First Quarter4Fri
5Sat10:001.211:570.74:300.76:200.36:538:05First Quarter5Sat
6Sun10:551.25:160.87:280.36:548:05Waxing Gibbous6Sun
7Mon1:390.711:55 AM1.26:090.88:310.26:548:04Waxing Gibbous7Mon
8Tue2:420.712:531.37:070.89:230.16:558:03Waxing Gibbous8Tue
9Wed3:210.71:451.38:020.810:050.16:558:02Waxing Gibbous9Wed
10Thu3:500.82:321.48:520.810:410.06:568:02Waxing Gibbous10Thu
11Fri4:160.83:171.59:370.711:130.06:568:01Full Moon11Fri
12Sat4:430.93:591.510:190.711:430.16:578:00Full Moon12Sat
13Sun5:111.04:401.511:010.66:577:59Full Moon13Sun
14Mon5:401.15:221.512:120.111:43 AM0.66:577:59Waning Gibbous14Mon
15Tue6:091.26:051.412:420.212:280.56:587:58Waning Gibbous15Tue
16Wed6:401.26:501.31:110.31:170.46:587:57Waning Gibbous16Wed
17Thu7:111.37:391.21:430.42:120.46:597:56Waning Gibbous17Thu
18Fri7:461.48:371.02:150.53:150.36:597:55Third Quarter18Fri
19Sat8:271.49:520.92:510.74:260.36:597:54Third Quarter19Sat
20Sun9:191.411:320.73:330.75:430.27:007:53Third Quarter20Sun
21Mon10:261.54:260.87:010.17:007:52Third Quarter21Mon
22Tue1:100.711:45 AM1.55:340.98:140.17:017:52Waning Crescent22Tue
23Wed2:160.81:001.66:510.89:150.07:017:51Waning Crescent23Wed
24Thu3:030.82:061.78:040.810:050.07:017:50Waning Crescent24Thu
25Fri3:420.93:051.79:080.610:480.17:027:49New Moon25Fri
26Sat4:171.03:571.710:060.511:250.27:027:48New Moon26Sat
27Sun4:501.24:461.711:000.47:037:47New Moon27Sun
28Mon5:231.35:321.612:000.311:50 AM0.47:037:46Waxing Crescent28Mon
29Tue5:541.46:161.512:340.412:400.47:037:45Waxing Crescent29Tue
30Wed6:261.46:581.31:070.51:310.47:047:44Waxing Crescent30Wed
31Thu6:581.57:421.21:400.72:240.47:047:43Waxing Crescent31Thu
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 1:29 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 neap phase. Tonight's moon is 52% 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 minimum.

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 First Quarter (52% illuminated). This places Grassy Key, north side, Florida Bay, FL in a neap tide cycle, so tidal ranges are near their weekly minimum 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