Guide
Reading a tide table on the Mississippi coast
Checked September 29, 2026 against NOAA Tides and Currents and NOAA’s National Ocean Service.
The Tides tile repeats NOAA’s predictions for the station nearest your town and, where there is one, what its gauge is measuring now. On this coast the tide is small, and the wind can move the water more than the Moon does. This page explains what the zero is, the shape of the tide here, which station each town reads, and how to read the gap between the prediction and the water.
Zero is not the bottom
Every height on the tile is measured from mean lower low water — MLLW — which NOAA defines as “the average of the lower low water height of each tidal day observed over the National Tidal Datum Epoch.” Because it is an average, many low tides fall below it: a prediction of −0.3 ft is not an error. A charted depth is also measured from MLLW, so a channel charted at 4 feet has less than that on a minus tide.
A small tide, usually once a day
NOAA’s National Ocean Service: “Some areas, such as the Gulf of Mexico, have only one high and one low tide each day.” That is a diurnal tide, which NOAA’s glossary describes as the tide “when only one high water and one low water occur during a tidal day.” In NOAA’s own tables for September 2026, Pass Christian had one high tide on 29 days, Bay Waveland on 26 and Pascagoula on 24. So most days the table shows one high and one low, and on some days two of each. Neither is a mistake.
The range is small. NOAA’s figure for each station is the great diurnal range, “the difference in height between mean higher high water and mean lower low water.” At every station this board reads it is between about a foot and a half and 1.8 feet: 1.79 at Bay Waveland, 1.53 at the Pascagoula NOAA Lab.
Which station each town reads
“Live gauge” means NOAA publishes the gauge’s measured level as it comes in; “prediction” means a table and nothing measured. This board reads six stations. The range is NOAA’s great diurnal range for that station.
| Town | Station | Range | Reading |
|---|---|---|---|
| Waveland | Bay Waveland Yacht Club 8747437 | 1.79 ft | Live gauge |
| Bay St. Louis | Bay Waveland Yacht Club 8747437 | 1.79 ft | Live gauge |
| Diamondhead | Bay Waveland Yacht Club 8747437 | 1.79 ft | Live gauge |
| Pass Christian | Pass Christian Yacht Club 8746819 | 1.73 ft | Prediction |
| Long Beach | Gulfport Harbor 8745557 | 1.73 ft | Prediction |
| Gulfport | Gulfport Harbor 8745557 | 1.73 ft | Prediction |
| Biloxi | Biloxi 8744117 | 1.78 ft | Prediction |
| D’Iberville | Biloxi 8744117 | 1.78 ft | Prediction |
| Ocean Springs | Ocean Springs 8743281 | 1.73 ft | Prediction |
| Gautier | Pascagoula NOAA Lab 8741533 | 1.53 ft | Live gauge |
| Pascagoula | Pascagoula NOAA Lab 8741533 | 1.53 ft | Live gauge |
| Moss Point | Pascagoula NOAA Lab 8741533 | 1.53 ft | Live gauge |
Two gauges measure the water on this coast: the Bay Waveland Yacht Club, on the Bay of St. Louis, and the NOAA Lab at Pascagoula. Every table between them is a prediction worked from each station’s own harmonic constants, with nothing measured.
Why the water is not where the prediction said
NOAA is direct about what a tide table leaves out:
“We can only predict the astronomical tides” — the pull of the Moon and Sun.
“We cannot predict the effect that wind, rain, freshwater runoff, and other short-term meteorological events will have on the tides.”
On a coast with a tide of under two feet, those effects can be bigger than the tide. The National Ocean Service: “Onshore winds may act to pile up water onto the shoreline, virtually eliminating low tide exposures”, and “strong offshore winds can move water away from coastlines, exaggerating low tide exposures.” This coast faces the Gulf to the south, so a steady south or southeast wind is onshore and holds the water up, and the north wind behind a front is offshore and pulls it down.
How big: between October 1, 2025 and September 29, 2026, NOAA’s hourly heights ran well away from the prediction. At Bay Waveland the water ran 3.2 feet above it and 2.9 below, against a daily range of 1.8. At Pascagoula it ran 2.6 feet above and 1.6 below. Both are more than the whole daily range.
So read the tile this way. Where the station has a live gauge, the measured level is the answer and the prediction is a guide to when it will rise and fall. Where it has predictions only, treat the table as the start of the question and look at the wind forecast. And a hurricane’s storm surge is a different thing altogether; it is the weather service’s warnings, not the tide table, that speak to it.
Sources
- NOAA Tides and Currents, tidal datums — MLLW and the great diurnal range
- NOAA Tides and Currents, glossary — the diurnal tide
- NOAA National Ocean Service, types and causes of tidal cycles — the Gulf’s diurnal tide
- NOAA National Ocean Service, what affects tides in addition to the Sun and Moon — onshore and offshore wind
- NOAA Tides and Currents, frequently asked questions — what a prediction can and cannot include
- Measured water levels, both live gauges the board reads: Bay Waveland Yacht Club, Pascagoula NOAA Lab
- NOAA’s datums for each station, which give the great diurnal range: for example Bay Waveland