canIswim

Sea temperature and swimming season in Mocha

The sea off Mocha is comfortable for swimming all year round — it never drops below 25.8°C, and peaks at 32.0°C in September.

Month by month

Sea temperature, the air you climb out into, and the wind that decides how that feels.

Sea temperature, air temperature, wind and daylight by month.
Month Sea Air Wind Feels What to wear
January 25.9°C 30.1°C 8.6 m/s Very comfortable none needed
February 25.8°C 30.1°C 8.8 m/s Very comfortable none needed
March 26.6°C 32.4°C 8.2 m/s Bath-like none needed
April 28.2°C 34.4°C 7.0 m/s Bath-like none needed
May 30.0°C 34.9°C 4.8 m/s Bath-like none needed
June 30.8°C 36.4°C 5.3 m/s Bath-like none needed
July 31.0°C 35.4°C 6.5 m/s Bath-like none needed
August 31.3°C 36.6°C 4.8 m/s Bath-like none needed
September 32.0°C 36.1°C 5.9 m/s Bath-like none needed
October 30.5°C 34.6°C 5.2 m/s Bath-like none needed
November 27.9°C 32.6°C 8.4 m/s Bath-like none needed
December 26.6°C 30.7°C 7.9 m/s Bath-like none needed

Air is the average daily maximum — roughly what you would meet swimming in the middle of the day. An arrow marks months where the air is colder than the sea.

When in the day can you swim?

Daylight and burn risk by month, in Asia/Aden local time.

MonthSunriseSunsetDaylightPeak UV
January 06:33 17:59 11h 25m 10.0
February 06:29 18:12 11h 43m 12.2
March 06:14 18:17 12h 03m 14.3
April 05:54 18:19 12h 26m 15.5
May 05:41 18:25 12h 44m 15.4
June 05:40 18:34 12h 54m 15.1
July 05:47 18:38 12h 50m 15.4
August 05:54 18:28 12h 34m 15.9
September 05:56 18:08 12h 12m 15.4
October 05:57 17:48 11h 51m 13.4
November 06:06 17:36 11h 31m 10.8
December 06:21 17:42 11h 21m 9.4

Open water burns faster than a beach: the surface reflects sunlight up at you, and sunscreen washes off in the first few minutes. A long swim under a UV index above 6 needs a rash vest more than it needs more cream.

What the bands mean

FromDescriptionIn practice
above 26°C Bath-like Warm enough that it offers no cooling at all
above 22°C Very comfortable Swimwear, no time limit for most people
above 19°C Comfortable Pleasant once you are in; most people swim happily
above 16°C Bracing Swimmable but short; many prefer a shorty wetsuit
above 12°C Cold Wetsuit territory. Unprotected swims should be brief
below 12°C Dangerous Cold shock risk. Specialist gear and supervision

Do you need a wetsuit in Mocha?

No. The sea here never falls below 25.8°C, so there is no month in which neoprene is the thing standing between you and a comfortable swim. A rash vest is worth having, but for the sun on your back rather than for warmth — the surface burns while you swim, and you will not feel it happening.

Other coastal cities in Yemen

Where these numbers come from, and what they miss

  • Open water, not your beach. The measurement is a satellite cell about 28 km across, centred 14.9 km from Mocha. Shallow bays and lagoons run warmer; exposed coasts with upwelling run colder, sometimes by several degrees.
  • Surface temperature. Below a few metres the sea is often noticeably colder, and in summer a warm surface layer can sit over much colder water.
  • A six-year average, not a thirty-year normal. Sea temperature varies little between years, so this is close — but it is not a climate normal, and any individual year will differ.
  • Averages hide storms. A monthly mean says nothing about the week a cold current arrives.

Full methodology, sources and known limitations