public function getWind($withUnit = false)
    {
        if (!$this->lastResponse || !isset($this->lastResponse['wind']['speed'])) {
            return array();
        }

        $response = array(
            'chill' => $this->lastResponse['wind']['chill'],
            'direction' => $this->lastResponse['wind']['direction'],
            'speed' => $this->lastResponse['wind']['speed'],
        );

        if ($withUnit) {
            $response['speed'] .= ' '.$this->lastResponse['units']['speed'];
        }

        return $response;
    }