I am trying to plan my route from south Lefkada (Greece) to Marzamemi south east coast, Sicilia on Saturday 24th August a distance of about 280 miles. My boat speed will be 7.5 / 8 knots.

I am confused as when I switch on ‘speed’ at 4ms at the bottom of the routing page I get NO cloud, RAIN OR LIGHTENING showing on my route.

When I switch of ‘speed’ I get cloud, RAIN and LIGHTENING showing up at between about 140 miles out for about approximately 70 miles, then it is clear again.

Could you please look at the two images attached and explain to me what I should be looking at for accuracy and why there is rain and thunder when I switch off speed and no )rain and thunder when I switch on speed at 4ms?

As you can appreciate I do not wish to get caught in thundery or rainy weather.

You help as to which option will give me best accuracy / realistic.