The Atlantic, can be very unpredictable, and whilst you can nearly guarantee warm hot weather in the Caribbean, basically anything can happen in the Atlantic.
As a rule I would expect the Spring trans Atlantic to Europe to have a high chance of hitting rough seas and rain type conditions. The Atlantic is colder than the Caribbean, and often weather systems prevail from USA to Europe, so the bad weather comes across.
There tend not to be any hurricanes in the Atlantic, albeit the tail end of one can occur.
The Atlantic takes a long time to warm up, so Summer and early fall, have a greater percentage chance of good weather.
The 2007 TA's followed this May bad crossing then August a great crossing.
The Med is generally more predictable, most likely good weather, but there are active storms, and I have been in bad weather in May, but if you are going July/August predict very hot weather. Maybe as strong as the Caribbean Rome for example can be in a heatwave.
Barcelona whilst hot can be very windy.
England and Baltic, well anything goes, we do not know day to day what will come even in high summer, it can rain, it can be sunny, it can be a mixture.
Cant help other than say prepare for anything.
Summary
- Eastbound TA, Possible high chance of bad weather upto Gibraltar, then higher chance of good weather.
- Westbound, quite a good chance of good weather.
- Med prepare of very hot weather, but occasional sharp storm.
- England, Anything,
- Baltic, Anything.