What causes the strongest winds on Ascension?

Ascension sits within the trade wind belt, a prevailing pattern of easterly surface winds found in the tropics, they are a warm steady breeze that blows almost constantly. Here on Ascension we are affected by the South Easterly trades. Trade winds were used by sailing ships to cross the world’s oceans, establishing trade routes hence the name.

The wind at the airhead averages 12-18 knots with gusts in the region of 20-24 knots all year round. There is some variation through the day, generally the wind builds through the morning to a peak late afternoon, it then eases through the evening, so it is at its slackest just before the sun comes up. This isn’t always the case though as bubbly cumulus clouds (the ones that look like cauliflower) and the dreaded drizzly showers can increase the wind speed at almost anytime of the day or night.  The lowest daily mean in any month is usually around 10 knots and the highest in the region of 20 knots. 

This week was an interesting week wind wise with some of the slackest winds I’ve seen in my 11 months on Ascension. To start the week, Monday, Tuesday and Wednesday saw unusually light winds of 02-14 knots, whilst on Friday and Saturday we experienced unusually high gusts of 31 knots in association with showers.

The strongest winds on Ascension Island are however not caused by a meteorological phenomenon but found when stood downwind of the RAF Policemen after a plateful of sprouts.