You always need to check it, yeah swell info can give you a "good" idea of how the waves will be but its never perfect. Today the forecast for Monmouth County said knee high, at the right sandbars there were really good chest high waves just rolling through and it was also super clean. Most guys don't check the waves if the forecast is down but you shouldn't do that, always check it. There was only 4 guys out and the wave was super fun. Sometimes it says chest and clean and its knee but guys will just paddle out just because the forecast says chest. You can't always trust it, always check!