Which has warmer water, Cancún or Cozumel?

Cancún averages 83°F over the year and Cozumel 84°F. In January it is 80°F vs 81°F; in July 84°F vs 86°F.

Which is less crowded?

Cancún is quietest in September and October; Cozumel in September and October.

Which has less sargassum?

Over a typical year, seaweed averages high in Cancún and high in Cozumel. Cancún is lightest in January and December; Cozumel in January and June.

Cancún vs Cozumel

Cozumel usually grades better in January and August, and the other months are close; Cancún never beats it by a clear margin. In winter (December to February) the two are close (both B). Seaweed: Cancún peaks high in August, Cozumel peaks high in October.

Month by month

A typical day in each month (median resort). Bold: better by a clear margin.

Month	Cancún	Cozumel	Water	Rain chance	Seaweed	Crowds	Storm risk
January	B	B+	80°F / 81°F	45% / 44%	Moderate / Moderate	Very busy / Very busy	Very low / Very low
February	B	B+	80°F / 80°F	38% / 37%	Moderate / Moderate	Very busy / Very busy	Very low / Very low
March	B	B	80°F / 81°F	37% / 39%	Moderate / Moderate	Packed / Packed	Very low / Very low
April	B	B	81°F / 82°F	28% / 34%	Moderate / High	Very busy / Very busy	Very low / Very low
May	B	B	82°F / 84°F	43% / 44%	High / High	Busy / Busy	Very low / Very low
June	B-	B-	83°F / 85°F	70% / 71%	High / Moderate	Busy / Busy	Very low / Very low
July	C+	B-	84°F / 86°F	61% / 57%	High / High	Very busy / Very busy	Low / Low
August	C	C+	85°F / 86°F	67% / 68%	High / High	Busy / Busy	Moderate / Moderate
September	C	C	85°F / 87°F	76% / 77%	High / High	Moderate / Moderate	High / High
October	B-	B-	85°F / 86°F	67% / 70%	High / High	Moderate / Moderate	Low / Moderate
November	B-	B	84°F / 84°F	54% / 59%	High / High	Busy / Busy	Very low / Very low
December	B	B	82°F / 82°F	48% / 46%	Moderate / High	Very busy / Very busy	Very low / Very low

Pairs of values read Cancún / Cozumel. From Veabird's year-ahead outlook: climate normals, the seasonal seaweed pattern, holiday crowds and storm history.

This week

Grades for the next few days at the resorts that usually do best this month.

Cancún

Holbox Island HotelsSatC+SunC+MonC-TueCWedC
Villas FlamingosSatC+SunC+MonC-TueCWedC
Villas DelphinesSatC+SunC+MonC-TueCWedC
Xaloc ResortSatC+SunC+MonC-TueCWedC

Cozumel

Secrets Aura CozumelSatD+SunC+MonBTueCWedC-
Presidente InterContinental CozumelSatD+SunC+MonBTueCWedC-
Iberostar CozumelSatDSunC-MonCTueCWedC-
Allegro CozumelSatDSunC-MonCTueCWedC-

Grades for the next few days from Veabird's beach forecast, updated Oct 3, 18:00 UTC. Higher is better: A+ to F.

Cancún & Isla Mujeres forecast · Cozumel forecast

Questions

Is Cancún or Cozumel better?: Cozumel usually grades better in January and August, and the other months are close; Cancún never beats it by a clear margin. In winter (December to February) the two are close (both B). Seaweed: Cancún peaks high in August, Cozumel peaks high in October.
Which has warmer water, Cancún or Cozumel?: Cancún averages 83°F over the year and Cozumel 84°F. In January it is 80°F vs 81°F; in July 84°F vs 86°F.
Which is less crowded?: Cancún is quietest in September and October; Cozumel in September and October.
Which has less sargassum?: Over a typical year, seaweed averages high in Cancún and high in Cozumel. Cancún is lightest in January and December; Cozumel in January and June.