Island Overview
Thursday 18 September is dry and warm across all of Crete. No rain is expected anywhere on the island, and afternoon highs reach between 25°C and 27°C depending on location. Overnight lows stay mild at 19 to 23°C, with the south coast retaining the most heat after dark. Summer is not gone yet.
North Coast, South Coast and the East
The sharpest contrast today runs east to west rather than north to south. Chania and Rethymno are under overcast skies this morning with no rain and light winds, particularly in Chania where gusts barely reach 10 km/h. Cloud is expected to thin through the day. Heraklion sits mainly clear at 26°C with a moderate 21 km/h northerly, and the resort strip from Hersonissos to Malia is partly cloudy with similar wind speeds.
The south coast, Ierapetra and Makrigialos, is fully clear with overnight lows above 21°C. Winds are stronger here at up to 30 km/h, but the sheltered bays face south and wave heights stay very low: 0.3m at Ierapetra and 0.5m at Makrigialos. The east, from Ag. Nikolaos and Elounda to Sitia, sees the strongest winds on the island today, peaking at 33 km/h in Sitia, with corresponding sea chop reaching 1.3m.
Mountain Conditions
Psiloritis and the Lefka Ori above Chania will run 6 to 8 degrees cooler than the coast. Visibility should improve through the afternoon as western cloud breaks up. A reasonable day for hiking at elevation; carry a layer for the drop in temperature after 15:00.
Sea Temperature, Wind and UV
Sea surface temperatures across all monitored points range from 25.6°C to 26.7°C, still genuinely warm for mid-September. The UV index peaks at 7.0 in Rethymno and sits between 6.75 and 6.9 elsewhere, placing it in the high category. The midday sun retains real intensity between 11:00 and 15:00, including beneath partial cloud. Wind is lightest in the far west and strongest in the east, where Sitia records today's island maximum at 33 km/h.
Swim Verdict
Swimming conditions are good to excellent across most of Crete. The south coast offers the calmest water, with Ierapetra's sheltered bays close to flat. North-coast beaches from Heraklion to Hersonissos carry manageable one-metre chop. Sitia and Elounda see the liveliest sea today, with 1.2 to 1.3m waves driven by the wind: safe for confident adults, but not the first choice for young children or inflatable gear.
Practical Tip for the Day
A UV index of 7 is easy to underestimate on a grey morning in Chania or a breezy afternoon in Sitia. Apply broad-spectrum sunscreen before going outdoors and reapply after every swim. The 11:00 to 15:00 window still earns its reputation across the whole island today, regardless of cloud cover.
