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 : 4:35 pm (0.4 ft)
Next high tide : in 3h 56m at 8:25 am (1.4 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 - Sep 1934

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Sat9:271.43:360.96:060.57:047:43Third Quarter1Sat
2Sun12:120.810:40 AM1.44:401.07:210.57:047:42Third Quarter2Sun
3Mon1:360.811:57 AM1.45:591.08:240.57:057:41Waning Crescent3Mon
4Tue2:190.91:021.47:121.09:110.57:057:40Waning Crescent4Tue
5Wed2:481.01:541.58:140.99:470.57:057:39Waning Crescent5Wed
6Thu3:111.02:381.59:050.910:170.57:067:38Waning Crescent6Thu
7Fri3:331.13:181.59:480.810:440.57:067:37New Moon7Fri
8Sat3:571.23:561.510:270.711:090.67:077:35New Moon8Sat
9Sun4:221.34:341.511:040.611:330.67:077:34New Moon9Sun
10Mon4:491.45:121.511:410.511:570.77:077:33New Moon10Mon
11Tue5:171.55:521.412:190.47:087:32Waxing Crescent11Tue
12Wed5:471.56:341.212:210.71:010.37:087:31Waxing Crescent12Wed
13Thu6:181.57:201.112:470.81:490.37:087:30Waxing Crescent13Thu
14Fri6:541.68:151.01:150.82:440.37:097:29Waxing Crescent14Fri
15Sat7:381.69:290.91:470.93:510.47:097:28First Quarter15Sat
16Sun8:351.611:100.82:271.05:090.47:097:27First Quarter16Sun
17Mon9:521.63:311.16:270.47:107:26First Quarter17Mon
18Tue12:380.911:22 AM1.65:071.17:360.47:107:25Waxing Gibbous18Tue
19Wed1:301.012:411.76:401.08:320.47:117:24Waxing Gibbous19Wed
20Thu2:091.11:491.77:560.99:170.57:117:23Waxing Gibbous20Thu
21Fri2:451.32:471.89:000.79:560.57:117:22Full Moon21Fri
22Sat3:191.43:411.79:560.510:320.67:127:21Full Moon22Sat
23Sun3:531.64:311.710:480.311:070.77:127:20Full Moon23Sun
24Mon4:271.75:191.511:380.211:410.77:127:18Full Moon24Mon
25Tue5:031.76:051.412:260.27:137:17Waning Gibbous25Tue
26Wed5:401.76:501.212:150.81:160.27:137:16Waning Gibbous26Wed
27Thu6:181.77:371.112:490.92:090.37:147:15Waning Gibbous27Thu
28Fri7:001.78:311.01:241.03:070.47:147:14Third Quarter28Fri
29Sat7:461.69:420.92:021.04:140.67:147:13Third Quarter29Sat
30Sun7:431.510:300.91:511.14:270.76:156:12Third 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 12:30 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 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