This hurricane season has been wild! Like us, many of you probably watched the projected path of Hurricanes Franklin, Lee and Nigel with a familiar foreboding sense of déjà vu. We spoke with Michelle Pitcher, the Director of the Bermuda Weather Service along with Deputy Director, Alex Young, to discuss.

We seem to have had a lot of unusual weather this year – a very wet summer and a lot of storms. What would you say is the underlying cause of this, or is this year a fluke?
This has been an unusually wet spring and summer, made even more noticeable by the past two being unusually warm and dry. We do not have any one underlying cause beyond normal climatic fluctuations. However, we do monitor trends and if we see that over 5, 10, 15 years we have been experiencing something different from the average, then that is when we start to consider affects from climate change. Remember average or normal conditions are just that – it does not mean we will not experience conditions outside of this.

Do you think this active storm season (and the active previous few years) represent the new normal?
In April 2021, the National Hurricane Center increased the number of cyclones for the average Hurricane Season. So yes, this is our new normal.

Is there any sense that the hurricane season’s peak is shifting earlier each year? Does that mean we can expect the season to taper off a little earlier (this year or overall)?
The official hurricane season for the Atlantic basin is from June 1 to November 30, but tropical cyclone activity sometimes occurs before and after these dates, respectively. The peak of the Atlantic hurricane season is September 10, with most activity occurring between mid-August and mid-October. Every year is unique as climate and weather factors dictate how active or quiet a hurricane season can be. This year we saw an uptick in tropical cyclone formation towards the end of August, which falls within the climatological peak for hurricanes in the Atlantic Basin.

The earlier onset of the peak of the hurricane season does not correlate to an overall earlier end to the season. As previously mentioned, climate and weather factors dictate how active or quiet a season can be.

Why do you think we’re seeing so many storms swirling around in the Atlantic?
We are within the climatological peak of the hurricane season which tends to see the formation of more storms. The peak this year was aided by a positive (wet) phase of the Madden-Julian Oscillation (MJO).

The MJO is an eastward moving disturbance of clouds, rainfall, winds, and pressure that traverses the planet in the tropics and returns to its initial starting point in 30 to 60 days, on average.

The MJO consists of two parts, or phases: one is the enhanced rainfall (or convective) phase and the other is the suppressed rainfall phase. Strong MJO activity often dissects the planet into halves: one half within the enhanced convective phase and the other half in the suppressed convective phase. These two phases produce opposite changes in clouds and rainfall and this entire dipole (i.e. having two main opposing centres of action) propagates eastward.

We seem to be seeing patterns in storms’ routes. What’s causing so many of them to follow in each other’s footsteps?
This year has been quite unusual with a weaker than normal Bermuda-Azores high, which usually steers the tropical cyclones further south and through the Lesser Antilles. This could be due to the positive (wet) phase of the MJO. The high typically weakens towards mid-September but has been almost non-existent through summer this year. As a result, majority of the tropical cyclones that formed east of the Lesser Antilles, passed well north of the islands. The steering pattern in the upper-levels of the atmosphere then unfortunately steered 3 tropical cyclones (Franklin, Lee and Nigel) towards our general area. It is however, unsual for an area to be impacted by 3 tropical cyclones within 3 weeks (Franklin, Idalia and Lee).

On the other hand, it should be noted that the pattern taken is typical of Cape Verde tropical cyclones which are most active from mid-August to early October. These storms typically form from tropical waves moving off the African coast.

Is there anything else you would like to share or that you think would be helpful for Bermudians to know?
It is easy to focus on the seasonal prediction of average or below or above activity for hurricane season. The level of activity does not equate to impacts or landfalls. If there is only 1 hurricane, but it is a category 3 that hits Bermuda, then that means we had a very impactful season. If there are 20 hurricanes and not a one affects Bermuda, then, impact wise, it is a quiet season for us. We are also talking about large scale features, hurricanes, that are affected by many other features that are both large and small. And while our technology improves every year, Nature is still Nature and does not always follow ‘the rules’. We need to always be prepared for each hurricane season regardless of how active or not it is predicted/forecast to be. We also need to remember that we have ‘weathered’ many tropical cyclones in the past and have not suffered the level of damage that other areas have seen. Bermuda is very resilient. Bermuda’s residents are very resilient and do not hesitate to reach out a helping hand before and after a storm.

Remember, you can follow the Bermuda Weather Service’s services at www.weather.bm.