If you take a look at mu site, you'll find a number of sites providing weather for Croatia. The Croatian VHF broadcast seems to be non-existent (or has been for the past two years). You might get the Italian one on VHF but have to wait for them to get round to the Adriatic as they do the Med first. These people send SMS: meteo
It's usually forecastable but there can be considerable local variations. More unpredictable is a 'neverin' from the NW, usually heralded by v dark horizon in that sector. It can whip up an unholy wind, usually with rain lasting an hour or two. As bad or worse than the bora.