Achosnich (Scottish Gaelic: Achadh Osnaich) is a crofting township in Ardnamurchan, Argyle within the Scottish council area of Highland.

Like much of the British isles, Achosnich has a Temperate Maritime Climate, with mild, somewhat dry summers and cold, wet winters.

Temperatures usually range from 2.4 °C (36.3 °F) to 16.8 °C (62.2 °F), but the all-time temperature range is between −5 °C (23 °F), which is mild for its latitude and 28 °C (82 °F), which is slightly cooler than expected for its latitude.

There is an average of 15 snow days per year, with 23 air frosts and a wind speed reaching a peak of 28 kilometres per hour (17 mph) in February.

The highest wind speed recorded was 120 kilometres per hour (75 mph), unusually recorded in July.