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

TIDE TIMES for Friday, September 18, 2026
The tide is currently rising in Grassy Key, north side, Florida Bay, FL.

Next low tide (tomorrow) : 3:00 am (1.2 ft)
Next high tide : in 39m at 10:41 pm (0.8 ft)
Sunset today : 7:24 pm
Sunrise tomorrow : 7:11 am
Moon phase : First Quarter (48% illuminated)
Tide Station Location : Station #8723921
Common Questions About Tides

Grassy Key, north side, Florida Bay, FL Tides - Jun 1871

< May 1871

Print this Tide Chart

Jul 1871 >

Date		High Tide				Low Tide				Sun		Moon	Date
Date		AM	ft	PM	ft	AM	ft	PM	ft	Rise	Set	Moon	Date
1	Thu	1:50	0.9	1:22	1.4	7:53	0.3	9:02	-0.4	5:38	7:12		1	Thu
2	Fri	2:48	0.9	2:06	1.5	8:35	0.3	9:53	-0.6	5:37	7:12		2	Fri
3	Sat	3:43	0.9	2:52	1.6	9:18	0.3	10:43	-0.7	5:37	7:13		3	Sat
4	Sun	4:36	0.8	3:41	1.6	10:02	0.3	11:35	-0.7	5:37	7:13		4	Sun
5	Mon	5:28	0.8	4:32	1.6	10:49	0.4			5:37	7:14		5	Mon
6	Tue	6:19	0.7	5:26	1.5	12:29	-0.6	11:40 AM	0.4	5:37	7:14		6	Tue
7	Wed	7:12	0.7	6:22	1.4	1:24	-0.4	12:39	0.5	5:37	7:15		7	Wed
8	Thu	8:07	0.8	7:24	1.2	2:21	-0.3	1:51	0.5	5:37	7:15		8	Thu
9	Fri	9:05	0.8	8:33	1.1	3:18	-0.1	3:14	0.5	5:37	7:15		9	Fri
10	Sat	10:02	0.9	9:51	1.0	4:12	0.1	4:36	0.5	5:37	7:16		10	Sat
11	Sun	10:53	1.0	11:11	0.9	5:02	0.2	5:51	0.4	5:37	7:16		11	Sun
12	Mon	11:36	1.1			5:49	0.3	6:55	0.2	5:37	7:16		12	Mon
13	Tue	12:21	0.8	12:14	1.2	6:32	0.4	7:50	0.1	5:37	7:17		13	Tue
14	Wed	1:20	0.8	12:49	1.2	7:13	0.5	8:36	0.0	5:37	7:17		14	Wed
15	Thu	2:09	0.8	1:22	1.3	7:51	0.5	9:17	-0.2	5:37	7:17		15	Thu
16	Fri	2:53	0.7	1:56	1.3	8:28	0.5	9:54	-0.2	5:37	7:18		16	Fri
17	Sat	3:32	0.7	2:30	1.3	9:02	0.5	10:31	-0.3	5:38	7:18		17	Sat
18	Sun	4:10	0.7	3:06	1.3	9:36	0.5	11:07	-0.3	5:38	7:18		18	Sun
19	Mon	4:47	0.7	3:43	1.3	10:08	0.5	11:43	-0.3	5:38	7:19		19	Mon
20	Tue	5:25	0.7	4:22	1.3	10:42	0.5			5:38	7:19		20	Tue
21	Wed	6:05	0.7	5:02	1.3	12:22	-0.3	11:20 AM	0.6	5:38	7:19		21	Wed
22	Thu	6:45	0.8	5:44	1.2	1:02	-0.2	12:04	0.6	5:39	7:19		22	Thu
23	Fri	7:27	0.8	6:31	1.2	1:44	-0.1	12:59	0.6	5:39	7:19		23	Fri
24	Sat	8:11	0.9	7:25	1.1	2:28	0.0	2:07	0.6	5:39	7:20		24	Sat
25	Sun	8:56	0.9	8:31	1.0	3:13	0.1	3:24	0.5	5:39	7:20		25	Sun
26	Mon	9:42	1.0	9:52	0.9	4:00	0.2	4:40	0.4	5:40	7:20		26	Mon
27	Tue	10:29	1.1	11:17	0.8	4:47	0.3	5:51	0.2	5:40	7:20		27	Tue
28	Wed	11:16	1.2			5:35	0.4	6:55	-0.1	5:40	7:20		28	Wed
29	Thu	12:35	0.8	12:04	1.4	6:25	0.4	7:55	-0.3	5:40	7:20		29	Thu
30	Fri	1:42	0.8	12:54	1.5	7:14	0.4	8:51	-0.5	5:41	7:20		30	Fri
Date		High Tide				Low Tide				Sun		Moon	Date
Date		AM	ft	PM	ft	AM	ft	PM	ft	Rise	Set	Moon	Date

Tidal Data Source: (8723921)

www.USHarbors.com

The US Harbors tide chart design is protected by copyright. It may be printed for personal use only.
Any commercial use, modification, redistribution, or repackaging without written permission is strictly prohibited.

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 48% 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 (48% 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

In The Zone: The Sabre 51 Salon Express

By US Harbors When Sabre Yachts completed construction of hull number 200 of its 48 Salon Express model, more than half the crew who built it had also worked on hull number one. The average tenure on that line was 12 years, and they produced a yacht that proved to… Learn More