Entry Date: 02.02.2024, at 14:00:00 hrs (local)

Cape Town - Walvis Bay

Fog

Image

PRID: 12916
LegID: 352
LegNo: 97
Latitude: S029°52.09'
Longitude: E015°32.06'
Day#: 1466
Log (Day): 122 nm
Log (Leg): 127 nm
Log (Total): 75139 nm
Days sailing: 3
Covered distance: 284 nautical miles
Distance to destination: 201 nautical miles
Weather: 10kn S wind, 1.8m swell, fog, 26 degree Celsius
Mood of the crew: tense

Similar to the African East coast, there is also a current at its West coast. But in contrast to the Agulhas current in the East, which runs North to South and carries tropical warm water, its counterpart, the Benguela current at the West site carries icy cold water form the antarctic regions.

When, like now, warm and relatively moist air is guided across the cold water, then the air is often cooled down over the water below its dew point and the result is fog.

We assume that airspeed is an other factor for the appearance of fog. The air needs to stay a certain period of time over the cold water in order to cool down below the dew point. So far, during the 25-35kn range that was not the case. But today with only 10kn of wind speed, the air stays long enough over the cold water for the appearance of fog.