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

TIDE TIMES for Wednesday, August 19, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.
Next low tide (tomorrow) : 3:33 am (0.8 ft)
Next high tide : in 1h 38m at 9:38 pm (0.8 ft)
Sunset today : 7:54 pm
Sunrise tomorrow : 6:59 am
Moon phase : First Quarter (46% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Apr 1933

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat7:400.56:431.02:22-0.112:430.56:156:39First Quarter1Sat
2Sun8:560.57:361.03:250.01:070.66:146:40First Quarter2Sun
3Mon10:490.58:501.04:370.02:130.76:136:40First Quarter3Mon
4Tue11:550.610:181.05:450.14:340.76:126:41First Quarter4Tue
5Wed12:270.76:410.16:030.66:116:41Waxing Gibbous5Wed
6Thu12:540.87:250.17:070.46:106:42Waxing Gibbous6Thu
7Fri12:381.11:220.98:010.18:000.26:096:42Waxing Gibbous7Fri
8Sat1:331.11:511.18:340.28:470.06:086:42Waxing Gibbous8Sat
9Sun2:251.12:221.29:050.29:33-0.36:076:43Full Moon9Sun
10Mon3:151.12:551.39:370.210:19-0.56:066:43Full Moon10Mon
11Tue4:041.03:311.410:090.311:07-0.66:056:44Full Moon11Tue
12Wed4:540.94:101.510:430.311:57-0.76:046:44Waning Gibbous12Wed
13Thu5:460.84:541.511:180.36:036:45Waning Gibbous13Thu
14Fri6:410.75:431.412:52-0.611:57 AM0.46:026:45Waning Gibbous14Fri
15Sat7:440.66:401.31:54-0.512:430.56:016:45Third Quarter15Sat
16Sun9:020.57:501.23:03-0.31:480.56:006:46Third Quarter16Sun
17Mon10:270.69:171.14:17-0.13:220.65:596:46Third Quarter17Mon
18Tue11:300.710:471.15:260.05:010.65:596:47Third Quarter18Tue
19Wed12:150.86:250.16:240.45:586:47Waning Crescent19Wed
20Thu12:041.112:521.07:120.27:300.35:576:48Waning Crescent20Thu
21Fri1:071.11:241.17:510.38:240.15:566:48Waning Crescent21Fri
22Sat1:591.11:531.28:250.39:09-0.15:556:49Waning Crescent22Sat
23Sun2:441.02:211.38:580.49:50-0.25:546:49New Moon23Sun
24Mon3:251.02:491.39:290.410:28-0.35:536:49New Moon24Mon
25Tue4:030.93:171.39:590.411:05-0.35:526:50New Moon25Tue
26Wed4:390.83:481.310:270.411:42-0.35:526:50New Moon26Wed
27Thu5:160.84:201.310:550.55:516:51Waxing Crescent27Thu
28Fri5:550.74:551.212:22-0.311:21 AM0.55:506:51Waxing Crescent28Fri
29Sat6:390.65:331.21:05-0.211:47 AM0.65:496:52Waxing Crescent29Sat
30Sun8:300.67:171.21:54-0.11:190.66:497:52Waxing Crescent30Sun
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 12:35 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 46% 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 (46% 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