Island Overview
August 20 brings a clean, dry day across Crete. No rain is forecast at any point from coast to mountain, and every part of the island is well into positive temperatures from the early hours. Maximum temperatures range from 28.8°C in Rethymno to 31.1°C at Makrigialos on the southern Lassithi coast, a spread of barely three degrees that makes this one of those uniformly warm August days the island is known for.
North Coast vs South Coast
The main contrast today sits between the two coastlines. Along the north, Heraklion starts the day under fog and Chania has a partly cloudy sky. Neither condition is unusual for August mornings when sea humidity meets warm air, and both should clear as the sun climbs. Winds along the north are moderate: Chania records the day's highest gusts at 14.9 km/h, Heraklion at 14.1 km/h. These are light meltemi conditions, enough to take the edge off the heat without disrupting beach plans.
The south tells a different story. Ierapetra, Makrigialos, and Sitia sit under clear skies with noticeably calmer winds. Ierapetra registers just 6.6 km/h. The south also holds more overnight warmth: Ierapetra's minimum of 24.1°C and Makrigialos at 23.8°C mean residents and visitors in these areas will feel the heat well before sunrise. Those sensitive to warmth at night may find the north slightly more comfortable for sleeping.
Mountain Zones
The White Mountains above Chania and the Psiloritis massif behind Rethymno and Heraklion act as the natural dividers producing this north-south split. At altitude, temperatures drop sharply, falling well below 20°C above 1,500 metres. Hikers on either range should carry a wind layer and start early to avoid midday heat on exposed ridges.
Sea, Wind and UV
Sea surface temperatures sit in a tight range across all monitored locations, from 25.9°C at Sitia to 27.1°C at Heraklion. Wave heights are negligible everywhere: the highest reading of the day is 0.26 metres. UV peaks between 7.7 and 8.0 across the island, placing every location in the high band on the standard index. Unprotected skin can burn faster than expected, including under the light cloud cover affecting the north this morning.
Swim Verdict
Swimming conditions are excellent at every location today. Sea temperatures in the mid-to-upper 26°C range are close to their seasonal peak, and waves present no hazard anywhere. The south coast's calmer surface makes it slightly better for snorkelling and paddleboarding, but the north is equally safe and comfortable for open-water swimming.
Practical Tip for the Day
Do not let the morning fog in Heraklion or the cloud in Chania delay your sun protection routine. UV will reach index 8 by midday regardless of the morning sky. Apply SPF 30 or higher before leaving your accommodation, reapply after every swim, and plan shade breaks between noon and 15:00. A hat and a full water bottle are not optional at these temperatures.
