One of open water swimming's great challenges is the weather. And Mother Nature has a firm grip on things here in New England, so you can expect a wide range of conditions from rain and fog to sun and breeze. Air temperatures may be as low as the mid-50s (F) on race morning and reach highs in the 90s on the beach at the finish line. Water temperatures typically range from 58 degrees F at the lighthouse up to 65 degrees F along the course. Our weather motto is: Prepare for the worst, hope for the best.
The Boston Light Swim will go on, rain or shine. We monitor local weather conditions closely in the days leading up to the swim, and we will only cancel the race in the event of lightning, heavy wind or thick fog that reduces visibility to unsafe distances. (If the Coast Guard issues a small craft advisory, we will likely cancel, and we’re very sorry, but we cannot refund race registration fees in the event of a cancellation.)
We take safety very seriously, and if conditions look dicey, we will call the event--in mid-run if we have to.
If the event must be canceled, we will send an email to all participants and post notification to our social media channels as soon as the determination is made. Please monitor the email address you used to sign up for the event in the days leading up to the swim for more information and any weather notifications we may send. If the event is called after boats have left the dock, we will send an email, post on social media and make repeated radio calls to alert all participating boats.
NOAA reports
If you want to have a look at conditions yourself, check out these local NOAA buoy reports:
Buoy #44013 real-time report (12 miles out, closest to BLS course location)
Temperature and wind
You can access the full marine forecast on Weather Underground
Water temperature
Check the Boston Buoy, ID#B44012 on Weather.com for updated water temperature data.
Tides
You can access detailed predictions for currents at specified locations at this link. You'll need to choose a location, such as Rainsford Island or Little Brewster Island to get accurate tide data.