Today I made a serious mistake: used to the idea that in the Dodecanese there are never clouds, and therefore storms, I limited myself to checking only the wind forecast. I saw that it would blow from the south, allowing me to sail north without having to zigzag. Then, while browsing social media, I noticed warnings of storms expected in the upper Dodecanese, exactly where I was supposed to go! I immediately checked my usual sites, Windy and Poseidon, and indeed I saw that storms with lightning were expected.


Wind forecast given by Windy and Poseidon; the second one always gives lower wind speeds.



Windy predicts thunderstorms on Tuesday night into Wednesday while Poseidon predicts them during the day on Wednesday.

CAPE Index during forecasted thunderstorms
The problem is that, as you can see from the images, the two apps give different predictions. Which one will be the right one? Which one should I consider? Since I am still relatively inexperienced, I prefer to consider the worst case scenario to avoid unnecessary risks.
In addition to wind, rain and lightning forecasts, I also started checking the CAPE index, which unfortunately many still neglect. This index indicates how much potential energy is available for convection, or for the rising of an air mass. The higher the humidity and temperature at the ground, the higher the index, and the greater the probability of significant thunderstorms. However, it is important not to consider this data in isolation, but to combine it with other thermodynamic indices and wind forecasts at different altitudes. For example, cold and dry currents at medium altitudes, combined with warm and humid air at low altitudes, will favor the formation of thunderstorms of a certain intensity.
In conclusione, sull’isola dove mi trovavo (Patmos) non ci sono stati temporali, solo un vento moderato. Da lontano, perĂ², si vedevano fulmini all’orizzonte. Non sono sicuro se sulle isole a nord, come Fourni, si siano verificati temporali significativi o meno. Io sono rimasto comunque in porto a dormire tranquillamente.