Pressure patterns for February 1984 snowstorm that paralyzed the eastern United States.
sweeping along the same track produced heavier snow-
falls in the eastern United States.
Impact of snowstorms
Heavy, northern hemisphere snowstorms have sub-
stantial effects. As soon as snow begins to fall, trans-
portation networks in the United States are disrupted.
Local roads can be completely closed off within hours
of a storm striking and, depending upon the severity of
the storm, closed for several days (Figure 3.22).
Accident rates increase 200 per cent above average
within a few hours of a storm. Geographically, motor
vehicle insurance rates reflect the likely incidence of
storms. During moderate falls, vehicles caught on
roads can become stranded and impede snow removal.
In extreme cases, stranded vehicles can become death
traps. Motors left idling for warmth can suffocate occu-
pants with carbon monoxide, while accompanying cold
temperatures can freeze people to death. In the severe
Illinois winter of 1977-1978, 24 people died in motor
cars from these causes.
Airports are also affected within hours, and can be
kept closed for several days because of the time
required to clear long, wide runways. Closure of major
airports such as Chicago can disrupt airline schedules
nationwide. Blocking of roads leads to closure of
schools, industry and retail trade. The effect on retail
Fig. 3.22 The effect of a heavy snowstorm on roadways in St John's,
Newfoundland (photograph from Canadian Atmospheric
trade, however, is often short-term because shoppers
usually postpone purchases until after the storm. In
fact, the seasonal onset of snow is seen in many
northern states as a blessing, because it triggers
consumer spending for Christmas. Purchase of winter
clothes, snow tires, and heaters can also increase.