The archipelago of Bermuda has a very mild climate due to the influence of the Gulf Stream, but it is not a tropical paradise, at least in winter.
Annual precipitation is quite abundant, being around 1,400 millimeters (55 inches). The rains are fairly evenly distributed over the seasons, since the flow of weather fronts which occur in winter is replaced by the tropical rains of the summer months. Anyway, the least rainy months are April and May, while the rainiest month is October.
Here is the average precipitation in Hamilton, the capital.
Hamilton - Average precipitation

In winter, from November to March, temperatures are very mild, with lows around 15/17 °C (59/63 °F) and highs around 20/22 °C (68/72 °F). There can be days with good weather, which, however, are not always guaranteed: in fact, there are about 11/13 days with rain per month, and there can be windy days as well.
Summer in Bermuda is hot and muggy, with highs around 30 °C (86 °F) in July and August, although the heat is tempered by the breeze. There are about 10/12 days with rain per month, but the rain in this season usually falls in the form of short and intense showers and thunderstorms, which break out in the evening and do not affect much the amount of sunshine.
Here are the average temperatures.
Hamilton - Average temperatures
Min (°C)161616172023242524211917
Max (°C)202020222427293029262421
Min (°F)616161636873757775706663
Max (°F)686868727581848684797570


In Bermuda, there are not many hours of sunshine from November to March, when there are many cloudy days, while from April to September, the percentage of sunshine is good. Here are the average sunshine hours per day.
Hamilton - Sunshine

The sea is cool in winter, when the water temperature is around 19/20 °C (66/68 °F), while it becomes pleasantly warm from June to October, with a maximum in August, when the water temperature reaches 28 °C (82 °F).
Bermuda - Sea temperature
Temp (°C)202019202124272827252322
Temp (°F)686866687075818281777372


Sometimes, the archipelago can be hit by hurricanes. The hurricane season runs from June to November, although they are more likely from August to October. Since the ocean at this latitude is not as warm as the Gulf of Mexico, hurricanes do not generally hit Bermuda at the peak of their violence, however, they can still bring strong winds and heavy rains.
Some hurricanes that hit Bermuda with considerable intensity were the "Hurricane of Havana and Bermuda" in October 1926, Hurricane Emily in September 1987, Fabian in August 2003, Arlene in August 1963, Fay and Gonzalo, both in October 2014, and Nicole in October 2016.

Best Time

Because of its favorable climate, you can visit Bermuda all year round, to relax, play sports or explore nature in winter, and for a beach holiday in summer.
In summer, however, there's some risk of hurricanes.
All in all, April and May seem to be the best months, especially May, at least with regard to weather conditions, since it is still a bit cool for swimming: the daytime temperature is around 24 °C (75 °F), while the sea temperature is around 21 °C (70 °F).

What to pack

From December to April: bring light clothes, but also a sweatshirt or sweater, a jacket and an umbrella.
From June to September: bring summer clothing, and a light sweatshirt and a light raincoat for thunderstorms.