the temperature may result in fog (Figures
11-10 and 11-11).
Plan for daylight hours of operation
if you are not comfortable with night operation.
Updates and Personal
Observations
Periodically check NOAA weather radio
(VHF) or public weather broadcasts.
Seek shelter if you observe lowering
and thickening clouds or squall lines.
Monitor humidity and temperature
changes. Falling temperatures may lead
to fog.
Procedures
When operating in restricted visibility, the
following procedures are rec ommended:
• Reduce speed; the Navigation Rules
require it. You should be able to stop your
boat within one-half the distance you can
see. If another vessel looms up ahead of
you and it is following the same precaution,
collision will be unlikely.
• All hands should be wearing life jackets. A
person in the water in a life jacket is more
easily seen, especially when visibility is
poor.
• Post lookouts, one on the bow and one on
the stern. The helmsman must concentrate
on the operation of the boat.
• Turn on your navigation lights.
• Sound the proper sound signals for your
vessel. Powerboats sound 1 prolonged (4
to 6 seconds) blast every 2 minutes. Sailing
vessels (no power) sound 1 pro longed
blast followed by 2 short blasts every 2
minutes.
• If necessary, briefly shut down your
engine to listen for sounds of nearby
boats and aids to navigation. If you hear
a signal, reply with your own signal, and
proceed cautious ly until you determine
their position. The direction of sound is
difficult to determine in a fog.
Section 11: Adverse Conditions and Emergencies 129
• Determine your position as accurately as
possible, and plot the safest course to your
destination. Try to navigate from one
lighted navigation aid to another. Avoid
a course that brings you close to hazards.
Never take undue risks to get home.
• If lost, anchor and wait for conditions
to improve. You will save fuel and avoid
becoming further disoriented.
Severe Weather and Winds
Before setting out, check the weather forecast,
preferably on the VHF NOAA weather
channel and use your personal observations.
Pay particular attention to potential
squall line thunderstorms. Monitor forecasts
for strong winds. If high waves or high
winds are predicted, wait for a better day.
Do not go into conditions that could be
beyond your boating ability or the capabilities
of your boat.
Listen to weather forecasts while on
the water. Keep an eye to the west; weather
usually changes from that direction. High,
dark clouds or a change in wind direction
or velocity often tell of threatening
weather. Excessive static on an AM radio is
caused by electrical activity in the air usually
associated with thunderstorms (Figure
11-12, next page).
If there are warnings of approaching
bad weather, try to find a safe harbor as
soon as possible. The approach of a storm
should cause immediate concern for the
safety of your craft and crew.
Severe Weather Procedures
Even a cautious skipper is caught in bad
weather occasionally. If forced to ride out
a storm, the following procedures are recommended:
• Have all hands put on life jackets. If on a
sailboat, fasten safety harnesses to a jackline
or a sturdy through-bolted fitting. (A
jackline is a stainless steel wire or nylon
strap running from bow to stern at the
middle of the deck.)
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