What to Look for in a Fog

Not seeing clearly is only half the problem. Not doing the right thing is the other problem.

Fog is a three-letter word for trouble and history proves this point all too well. In 1956 the Italian luxury liner Andrea Doria was slammed into by the Stockholm, a Swedish liner in a thick fog off the coast of Nantucket. Fifty people died as a result of the collision. More recently and with much less tragedy, two lobster fishermen became lost in a heavy fog near Woods Hole, Massachusetts last year and had to be rescued by the U.S. Coast Guard. So fog knows no size of boat to be dangerous. The decisions that are made by those on board a boat in fog, however, can make this forbidding weather phenomena possibly fatal.

Fog is a low cloud. It occurs when cool water meets warm and moist air from land. One way to predict fog is by watching the temperature and the dew point (both are given in weather segments on the radio and TV. Dew point is also available using this formula: temperature X humidity + temperature divided by 2 ADD:or you can find it on the Internet at www.nws.noaa.gov and click on U.S. cities 3-day forecast). ENDADD When they are within six degrees of each other and the temperature continues to fall, you can usually expect fog within a few hours. In a majority of instances where fog is found, the wind is less than 10 knots. In other words, it sticks around until either the wind or temperature increases.

Fog is most prominent along the Pacific coastline (Los Angeles and south from September through February and north of L.A. from July through October). On the other side of the country it is found most often in Maine during the summer months (20% of the year Maine has fog). Interestingly enough, fog doesn't occur as often in Florida as it does in other parts of the country (Great Lakes). The area with the most days of fog (106) in the country is Cape Disappointment, Washington (see February/March 2001 issue). San Francisco which is known for fog around the Golden Gate Bridge has only a meager 18 days of poor visibility because of a low cloud.

The seasoned boater will suggest taking a lay day or reschedule a fishing trip if fog is forecast. But many boaters figure it will eventually lift, which is true. And it is here where many boaters get into trouble because fog is said to have a mind of its own and will stick around longer than expected. "It is," as the saying goes," the guest who is never invited and then never knows when to leave." This is why trailer boaters should know what to do while waiting for fog to get the message.

(1) If you are on the water and can see the fog bank moving in, start making a record of where you are. Get a chart out and mark your location. If you have a GPS, mark your location as a waypoint and use it to guide you back to the boat ramp or marina. It is extremely important to have set the ramp or marina approach as waypoints as well. If you haven't, this isn't the time to start looking up the coordinates and entering them into the GPS. This is also not the time to be out of batteries for the GPS. Carry extras every time you are going out on the boat. If you use loran, this is the time to know how to plot a course back to the ramp.
If you don't have a GPS or loran, then you are going to rely on your compass and/or depthfinder. Again, mark your location and determine the direction you will need to follow back to the ramp. Know the markers you will be passing as you near the ramp.

(2) If possible, post a lookout at the bow and let this person know what reference points they should be looking for as you head for port. From time to time, turn off the engine and listen for other horns and bells, traffic sounds which can indicate nearness to a highway and land or the sound of waves breaking. The latter can mean you are close to a beach or a rocky shoreline.

(3) Go slow. Excessive speed in poor visibility is asking for trouble. You are in the fog now so it doesn't matter anymore about trying to outrun the fact.

(4) If you aren't sure of your location or if markers don't appear as expected stop the boat and drop the anchor. But be absolutely certain you are not in a shipping channel or in the way of other boats that are trying to make port. In the event you do see another boat, follow them in if possible.

(5) Turn on your lights and have your horn or bell at the ready. If an oncoming boat can't see you, they are going to have to hear you in order to avoid a collision. You are required to do a four-second blast of the horn every 2 minutes while underway in fog. On the Great Lakes the rule is three short blasts every minute. Check with the Coast Guard or Power Squadron for local regulations regarding operating in poor visibility.

(6) Monitor Channel 16 for possible radio contact by other vessels that are in need of assistance or are in range of your horn and want to make sure you are aware of their location.

Navigating in fog requires common sense and, at times, some navigational creativity. It is important to know your position at all times. Be aware that tides and currents are going to push you off course so remember to factor this movement into the intended destination. If you are near shipping channels, do whatever it takes to stay out of the path of commercial traffic which has a difficult time stopping even with clear visibility.

By the time this uninvited guest decides to get out of the chair, having had some skills on the water will ensure you're still in the room when it walks through the door. Just know it will probably come back and visit again.