Weather Watch:  December 2004

PADDLING HAZARDS ASSOCIATED WITH COLD FRONTS

Cold fronts are boundaries between two masses of air originating from
two different locations.  For example, in the central and eastern
United States, cold fronts often separate cold air blowing from the
north or west from Canada and warm moist air blowing from the south.
A strong cold front is usually characterized by a large air
temperature decrease, an abrupt wind shift, a minimum in atmospheric
pressure, and the passage of a shallow cloud line called a rope cloud.
The increasing wind speed, change in wave orientation on the water
surface, and the approach of a rope cloud are the best ways to
identify the approach of a cold front on the open water.

Cold fronts can be particularly dangerous to paddlers because of the
wind.  Several hours before a cold-frontal passage, the warm winds may
strengthen.  Right after frontal passage, the cold winds may be strong
and gusty from the north and west.  These may make navigation
difficult, especially into the wind.  The abrupt shift in the wind at
the front may produce a confused sea with steep, irregular waves.  The
strong cooling with the cold-frontal passage may also catch paddlers
unaware, leading to hypothermia due to the cold wind and sea spray
from breaking waves.  Significant icing may occur if the air blowing
spray is below freezing.

<-David Schultz, NOAA/National Severe Storms Laboratory, Norman, Oklahoma>