Weather on St Helena is classed as tropical however it can vary from time to time throughout the year. There is no weather forecasting done on St Helena but there is a Meteorological station that collects weather surface and upper air data that is located at bottom woods since 1974 after the Station was moved from it old location at Hutt’s Gate.
The St Helena Airport will operate its own weather data forecasting for flights arriving and departing the Island.
The weather don’t vary much on a daily basis but it is always known for the temperatures to be a few degrees warmer in The Jamestown and the Half Tree Hollow areas compared to the country areas. The average temperature that was reported in a recent report showed that temperatures near the airport ranged from 14 to 25 degrees. The winter months starts at the end of June and the coldest months are normally recorded around July and August.
The sunny weather tends to be from December through to June with the average sunshine hours of around 130 hours a month.
The winds tend to be of average speeds throughout most of the year and normally stay well below 15 – 20 knots, but there are times when there are abnormal changes and occasionally winds can be a bit stronger but strong tropical storms are uncommon.
However, on the 5th September 2007 a record wind speed was recorded with gust up to 55 Mph which caused disruption to some roads and communications for short periods.
On the 31st of May 2008 a record rainfall was recorded and this caused flooding on some roads and minor damages to property.
From the 1st January 2015 – 01 January 2016. St. Helena experienced drier, hotter and slightly windier conditions than the past 5 years.
The island has approximately seven miles of leeward side where the sea conditions most of the year round is very calm and it is said to be a divers and fishermen paradise. Whereas on the windward side where most of the weather is prevalent the seas are much stronger most of the time.
The leeward side is most affected by high swells around January and February each year, this can make landing on St Helena very difficult and hazardous. Due to the deep seas around St Helena there is little variation between high and low tides usually around 0.9 of a metre difference most of the time.
At the time of writing a breakwater is been constructed in Rupert’s Valley to provide safe landing and cargo operations.