def recalculate_winds
      wind_sum = @winds.collect { |w| w[:wind] }.inject(0) { |b, i| b + i }
      @wind = wind_sum.to_f / @winds.size
      if @winds.size == 1
        @wind_direction = @winds.first[:wind_direction]
      else
        @wind_direction = nil
      end
    end
def recalculate_winds
      wind_sum = @winds.collect { |w| w[:wind] }.inject(0) { |b, i| b + i }
      @wind = wind_sum.to_f / @winds.size
      if @winds.size == 1
        @wind_direction = @winds.first[:wind_direction]
      else
        @wind_direction = nil
      end
    end
Calculate wind parameters, some metar string has multiple winds recorded