There are numerous weather sites you can consult. You can look at the lightning site I linked to, and google "St. Martin Radar weather" to get live radar precipitation reports. Even the NOAA satellite images contain this front. It won't be a major thing and most likely shortlived; but if you do go to a beach keep an eye out to the east for dark clouds and make sure to get under cover before those clouds arrive. I've been a pilot and flew gliders and sailed oceans and think I'm pretty knowledgeable about the weather, probably a bit more than a concierge at a resort Just looking at the clouds here right now and feeling the strong breeze, and not having seen the lightning site, I would say that we were in for some rain as a cold front passes. One just never knows ahead of time how strong it'll be or even if it misses St. Martin completely (and hits Anguilla...).

Just keep an eye out on the weather and don't get surprised, that's all I wanted to post.