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 4h 40m 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 - Apr 1967

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat9:300.58:051.13:27-0.32:120.56:156:39Third Quarter1Sat
2Sun11:200.59:301.04:44-0.13:370.66:146:40Third Quarter2Sun
3Mon12:270.66:01-0.15:130.66:136:40Third Quarter3Mon
4Tue1:070.77:060.06:350.56:126:41Waning Crescent4Tue
5Wed12:161.01:370.87:530.17:390.46:116:41Waning Crescent5Wed
6Thu1:121.12:010.98:290.18:290.36:106:41Waning Crescent6Thu
7Fri1:581.12:231.09:000.29:110.16:096:42Waning Crescent7Fri
8Sat2:371.12:451.19:280.29:490.06:086:42New Moon8Sat
9Sun3:141.13:081.19:540.210:24-0.16:076:43New Moon9Sun
10Mon3:501.03:321.210:190.310:58-0.26:066:43New Moon10Mon
11Tue4:261.03:581.210:430.311:32-0.26:056:44New Moon11Tue
12Wed5:040.94:261.211:050.46:046:44Waxing Crescent12Wed
13Thu5:440.84:551.212:09-0.311:28 AM0.46:036:44Waxing Crescent13Thu
14Fri6:280.75:271.212:50-0.311:51 AM0.56:026:45Waxing Crescent14Fri
15Sat7:210.66:061.21:38-0.212:190.56:016:45Waxing Crescent15Sat
16Sun8:300.56:551.12:36-0.212:550.66:016:46First Quarter16Sun
17Mon9:590.58:051.13:45-0.11:580.76:006:46First Quarter17Mon
18Tue11:130.69:381.14:560.03:470.75:596:47First Quarter18Tue
19Wed11:590.711:081.16:000.05:260.65:586:47Waxing Gibbous19Wed
20Thu12:350.96:540.06:430.45:576:48Waxing Gibbous20Thu
21Fri12:231.21:091.07:390.17:460.15:566:48Waxing Gibbous21Fri
22Sat1:261.21:421.28:190.18:42-0.25:556:48Waxing Gibbous22Sat
23Sun2:241.22:171.38:570.29:34-0.45:546:49Full Moon23Sun
24Mon3:191.12:541.49:340.210:24-0.65:546:49Full Moon24Mon
25Tue4:111.13:331.510:100.311:14-0.75:536:50Full Moon25Tue
26Wed5:030.94:141.510:470.35:526:50Waning Gibbous26Wed
27Thu5:550.84:591.512:06-0.611:24 AM0.45:516:51Waning Gibbous27Thu
28Fri6:490.75:471.41:01-0.512:050.55:506:51Waning Gibbous28Fri
29Sat7:510.66:401.32:00-0.412:530.55:506:52Third Quarter29Sat
30Sun10:070.68:431.24:06-0.23:000.66:497:52Third Quarter30Sun
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