Short answer: the strongest light beams in the cenotes of Tulum and Playa del Carmen happen around solar noon, which on this coast falls between 12:33 and 13:04, never at 12:00. The sun is highest in May and July, when it passes almost straight overhead, and lowest in December, when it never climbs above about 47°.
We calculated the position of the sun for every month of the year at Tulum, using the NOAA solar position formulas. Here is what the numbers say, and what they mean for your dive.
Solar noon and sun height, month by month
Values for the 15th of each month in Tulum (Quintana Roo stays on UTC−5 all year, with no daylight saving time). Playa del Carmen is within a minute or two of these times.
| Month | Solar noon | Max sun height |
| January | 12:58 | 48° |
| February | 13:04 | 57° |
| March | 12:59 | 67° |
| April | 12:50 | 79° |
| May | 12:46 | 88° |
| June | 12:50 | 87° |
| July | 12:56 | 88° |
| August | 12:55 | 84° |
| September | 12:45 | 73° |
| October | 12:35 | 62° |
| November | 12:35 | 52° |
| December | 12:45 | 47° |
Around 21 May and 23 July the sun is directly overhead at noon. That is when light can drop straight down a narrow opening.
Why the height of the sun matters
A light beam only forms when sunlight can pass through the opening of the cenote and reach the water. The higher the sun, the more vertical the light, and the deeper it travels into a narrow hole. In December, with the sun at 47° at best, a lot of that light hits the rock walls instead of the water. In May, it falls almost straight in.
Every cenote is different, though. The shape and size of the opening matter as much as the sun. A wide, open cenote gets light most of the day; a small hole above a deep cavern only lights up for a short window around noon.
Two things most divers don’t know
1. Noon is not 12:00
Quintana Roo sits far to the west of its time zone, so the sun reaches its highest point between 12:33 and 13:04 depending on the month. If you want the light, aim for that window, not for the clock.
2. The brightest months are not the busiest ones
Most visitors come between December and March, when the sun is at its lowest. The light-beam season is really late April to early June: the sun is high and the rainy season, with its clouds, has not started yet. July has the same sun height, but more cloudy afternoons.
Best cenotes by season: our guides’ picks
Winter (November to March)
The sun stays lower, so we favor open, bright cenotes where daylight fills the water all day:
- Chac Mool (Kukulkán), one of the brightest cenotes we dive. Combo: Kukulkán + Little Brother.
- El Edén, a wide, open cenote. Combo: El Edén + Chikin Ha.
- Casa Cenote, open water near Tulum. Combo: Casa Cenote + Angelita.
Summer (April to October)
The sun climbs almost straight overhead, which is when light can drop down vertical openings:
- The Pit, the classic light-beam dive. Combo: The Pit + Dos Ojos.
- Maravilla, a big open sinkhole with a halocline at 28 m (from Playa del Carmen only).
- Dreamgate, our guides’ summer pick. Combo: Carwash + Dreamgate.
How we use this on our dives
When light is the reason you came, tell us. We can plan the day so the cenote with the best light opening is dived closer to solar noon. Clouds and water conditions still decide the final show, so nobody can promise a beam, but timing gives you the best chance.
Ready to plan your dives? Fill in your short dive profile and we will suggest the right cenotes for your dates.
