![Mont Saint-Michel Tidal Bore: 2026 Mascaret Dates and Viewpoints](/images/post-covers/mont-saint-michel-tidal-bore-mobile.jpg) Blog Mont Saint-Michel Tidal Bore: 2026 Mascaret Dates and Viewpoints ================================================================ Orkhan Farmanli · Founder of montsaintmicheltides.com · August 23, 2026 > **TL;DR:** The mascaret is Mont Saint-Michel's tidal bore, a wave that runs up the rivers of the bay at the head of the rising tide on spring-tide days. The strongest remaining 2026 window is **11 to 13 September** (coefficients up to **102**); **27 October** matches it on paper at coefficient **100** but runs after dark. Arrive at Le Grouin du Sud **1h30** before the high tide time, or on the Mont itself **2h** before. From late October most of the bore's run happens in darkness, so September is the last comfortable daylight window of the year. What is the mascaret at Mont Saint-Michel? ------------------------------------------ When a strong flood tide funnels into a narrowing river mouth, the front of the incoming water steepens into a visible wave that travels upstream against the current. In the Bay of Mont Saint-Michel this wave, the mascaret, runs up the Sée, the Sélune, and the Couesnon. The [tourist office](https://www.ot-montsaintmichel.com/je-decouvre/nos-essentiels/les-grandes-marees-et-le-mascaret-grand-spectacle-de-la-nature/) describes it as a wave that can reach several tens of centimetres, forming on the rising tide during spring tides. That "spring tides" condition is the whole planning problem. The tourist office publishes no coefficient threshold for the bore, so the dates below use this site's spring-tide definition: every day with a tidal coefficient of **95 or above**, derived from [SHOM](https://www.shom.fr) predictions and listed in full on the [spring tides overview](/spring-tides-2026). The higher the coefficient, the stronger the flood and the better defined the wave, so the **coefficient 100+** cycles are the ones to travel for. The remaining 2026 mascaret dates --------------------------------- Eighteen spring-tide days remain in 2026 after 23 August. Each day has two rising tides, so most dates give two chances; the few cycles below coefficient 95 in the table are ordinary tides, listed for completeness. Both high tides are in legal French time (CEST through 24 October, CET from 25 October) with the coefficient of their cycle; the bore passes each viewing point 30 minutes to 2 hours **before** these times, depending on the site (offsets in the next section). DateMorning high (coef)Evening high (coef)Thursday 10 September07:28 (90)19:43 (95)Friday 11 September08:11 (98)20:25 (**101**)Saturday 12 September08:49 (**102**)21:02 (**101**)Sunday 13 September09:24 (**100**)21:36 (97)Sunday 27 September08:20 (95)20:37 (97)Monday 28 September08:54 (99)21:12 (99)Tuesday 29 September09:28 (98)21:46 (96)Saturday 10 October07:42 (94)19:57 (95)Sunday 11 October08:18 (95)20:32 (95)Monday 26 October06:47 (95)19:08 (98)Tuesday 27 October07:25 (99)19:47 (**100**)Wednesday 28 October08:03 (99)20:27 (96)Wednesday 25 November07:02 (96)19:30 (97)Thursday 26 November07:47 (97)20:16 (96)Thursday 24 December06:50 (91)19:23 (95)Friday 25 December07:41 (97)20:14 (99)Saturday 26 December08:31 (99)21:04 (98)Sunday 27 December09:19 (96)21:51 (93)**12 September** doubles as the last of the year's three island days, when the tide also submerges the causeway around the Mont; the [2026 island days page](/island-days-2026) has that date's full schedule. These are predictions for calm weather. Wind and atmospheric pressure move the real water level either way, so a windy low-pressure day can sharpen the bore and a calm high-pressure day can flatten it. Where to watch the tidal bore: seven viewing points --------------------------------------------------- The [tourist office lists seven observation sites](https://www.ot-montsaintmichel.com/je-decouvre/nos-essentiels/les-grandes-marees-et-le-mascaret-grand-spectacle-de-la-nature/) with a recommended arrival time before high water. The bore reaches the upstream river sites well before the tide peaks at the Mont, which is why the offsets differ so much. Viewing pointArrive before high waterLe Mont-Saint-Michel (ramparts and footbridge)**2h00**Le Grouin du Sud, Saint-Léonard**1h30**La Roche Torin, Courtils**1h15**Le Rivage, Vains**45 min**Le Gué de l'Épine, Val-Saint-Père**45 min**Le Pont de Marcey-les-Grèves**30 min**Le Pont de Pontaubault**30 min**The routine is simple: 1. Take the high tide time for your date from the table above. 2. Subtract the offset for your chosen site. 3. Be in place a little earlier still. Le Grouin du Sud is the classic choice: a headland over the Sée estuary where the wave arrives early and the view runs the width of the bay. On the Mont itself you are not watching a river wave but the flood surrounding the rock, which is why the recommended arrival stretches to two hours. The catch: autumn tides run in the dark --------------------------------------- A detail no schedule mentions: daylight. The bore is only a spectacle if you can see it, so run the arithmetic for your site against sunset, which in the bay slides from about **20:25** in mid September to **17:55** in late October and **17:14** by Christmas (sun times computed for the bay's own coordinates, the same calculation the weather page uses). In September the sums still work. The evening bore reaches Le Grouin du Sud between 18:13 and 20:16 across the seven dates, in daylight or at dusk on all but the 29th. The September morning highs from the **11th** onward peak after sunrise, between 20 minutes and 1h45 into the day depending on the date, so the closer your site sits to the Mont's high-water time, the more light you get; the 10 September morning cycle comes before sunrise everywhere. The **10 to 11 October** evening cycle is the last easy one: the wave passes Le Grouin du Sud at 18:27 and 19:02 on those dates, still ahead of the roughly 19:25 sunset. After the clocks change in late October, the picture flips. Evening highs between 19:08 and 21:51 against sunsets before 18:00 push the evening bore into darkness; only the longest-offset sites on **26 October** still catch the last light. The mornings are no better: the 26 to 28 October highs peak between 06:47 and 08:03 against a sunrise around 07:45, and in November and December the wave passes every viewing point before or around sunrise. In practice, 2026's daylight mascaret season ends in mid October. Before setting out, check the current tide state and the countdown to the next high water on the [live tide page](/now), and weigh the forecast against your date with the [weather and tides guide](/blog/mont-saint-michel-weather-and-tides). Watch from the bank, not the channel ------------------------------------ The mascaret looks gentle and is not. The [tourist office notes](https://www.ot-montsaintmichel.com/je-decouvre/nos-essentiels/les-grandes-marees-et-le-mascaret-grand-spectacle-de-la-nature/) that kayakers do surf the wave, and adds that it takes a trained athlete, because the force of the current is surprising and can knock them off balance. For everyone else the rule is the one that governs the whole bay: watch from the listed banks and bridges, never from the river channels or the flats. The flood behind the wave moves faster than a person walks on wet sand, and quicksand zones shift with every tide. If you want to be out in the bay at all, go with a licensed guide, and never on a spring-tide day. You might also like ------------------- - ![Weather and Tides at Mont Saint-Michel: How to Pick Your Day](/images/post-covers/mont-saint-michel-weather-and-tides-mobile.jpg) Aug 23, 2026 [ Weather and Tides at Mont Saint-Michel: How to Pick Your Day ](https://montsaintmicheltides.com/blog/mont-saint-michel-weather-and-tides)Tide times are fixed a year ahead, but the Mont Saint-Michel weather forecast only reaches nine days. How to join the two and pick a day you can see. - ![Is the Mont Saint-Michel Bay Walk a Hike? What It Involves](/images/post-covers/walking-across-mont-saint-michel-bay-mobile.jpg) Aug 01, 2026 [ Is the Mont Saint-Michel Bay Walk a Hike? What It Involves ](https://montsaintmicheltides.com/blog/walking-across-mont-saint-michel-bay)Walking across Mont Saint-Michel bay is a real hike: 13 to 15 km on the seabed, about 6 hours, and in practice always guided. Costs, kit, and timing. - ![Is a Day Trip to Mont Saint-Michel Worth It? How to Plan Your Timing (2026)](/images/post-covers/is-a-day-trip-to-mont-saint-michel-worth-it-mobile.jpg) Jul 18, 2026 [ Is a Day Trip to Mont Saint-Michel Worth It? How to Plan Your Timing (2026) ](https://montsaintmicheltides.com/blog/is-a-day-trip-to-mont-saint-michel-worth-it)A day trip from Paris gives you up to eight hours on the rock, which is plenty for the abbey, the ramparts, and the village. What it cannot give you is the big evening tide: on the biggest days of 2026 the water peaks after the last coach has left. Here is how to decide. [ Mont Saint-Michel Tides ](https://montsaintmicheltides.com)SHOM tide predictions for the bay, refreshed every year. montsaintmicheltides.com Browse -------- - [Today's tides](https://montsaintmicheltides.com#hero-heading) - [Now](https://montsaintmicheltides.com/now) - [Calendar](https://montsaintmicheltides.com/2026-tides) - [Spring tides](https://montsaintmicheltides.com/spring-tides-2026) - [Weather](https://montsaintmicheltides.com/mont-saint-michel-weather) - [Blog](https://montsaintmicheltides.com/blog) - [About](https://montsaintmicheltides.com/about) - [FAQ](https://montsaintmicheltides.com#faq-heading) - [Terms and Conditions](https://montsaintmicheltides.com/terms) Sources --------- - [ SHOM ↗ ](https://maree.shom.fr/) Source and accuracy. Predictions: SHOM (n° 2025-209), reference port Saint-Malo, distributed by the Office de Tourisme Mont Saint-Michel, Normandie. Times are in legal French time (CET in winter, CEST in summer). Strong onshore winds and low atmospheric pressure can raise actual water levels above prediction. The Tourist Office classifies "Mont becomes an island" days using local bay dynamics, not a simple coefficient threshold. Always verify on site before crossing. © 2026 montsaintmicheltides.com Last updated: 2026-08-23 Built with ♥ by [Orkhan Farmanli](https://github.com/orkhanfarmanli/)