function _weather_parse_sky_condition in Weather 7

Extract sky condition information.

Parameters

string $metar_raw: Raw METAR data to parse.

object $metar: METAR data object, may be altered.

1 call to _weather_parse_sky_condition()

weather_parse_metar in ./weather_parser.inc

Parses a raw METAR data string.

File

./weather_parser.inc, line 261

Retrieves and parses raw METAR data and stores result in database.

Code

function _weather_parse_sky_condition($metar_raw, &$metar) {

  // The ordering of cloud covering is as follows:
  // 0, CLR: clear
  // 1, FEW: few
  // 2, SCT: scattered
  // 3, BKN: broken
  // 4, OVC: overcast
  if (preg_match('/^' . '(FEW|SCT|BKN|OVC)([0-9]{3})' . '(CB|TCU)?(\\/\\/\\/)?' . '$/', $metar_raw, $matches)) {
    switch ($matches[1]) {
      case 'CLR':
        $metar->sky_condition_order[] = 0;
        $metar->sky_condition_text[] = 'clear';
        break;
      case 'FEW':
        $metar->sky_condition_order[] = 1;
        $metar->sky_condition_text[] = 'few';
        break;
      case 'SCT':
        $metar->sky_condition_order[] = 2;
        $metar->sky_condition_text[] = 'scattered';
        break;
      case 'BKN':
        $metar->sky_condition_order[] = 3;
        $metar->sky_condition_text[] = 'broken';
        break;
      case 'OVC':
        $metar->sky_condition_order[] = 4;
        $metar->sky_condition_text[] = 'overcast';
        break;
    }
  }
  elseif (preg_match('/^' . '(CLR|SKC|CAVOK)' . '$/', $metar_raw, $matches)) {
    $metar->sky_condition_order[] = 0;
    $metar->sky_condition_text[] = 'clear';

    // CAVOK implies a visibility of 10 km, there's no extra visibility section.
    if ($matches[1] == 'CAVOK') {
      $metar->visibility = 10000;
    }
  }
  elseif (preg_match('/^' . '(NSC|NCD)' . '$/', $metar_raw, $matches)) {

    // NSC means no significant clouds,
    // NCD is from automatic stations, no cloud detected
    // The ordering is equivalent to "FEW"
    $metar->sky_condition_order[] = 1;
    $metar->sky_condition_text[] = 'no significant clouds';
  }
  elseif (preg_match('/^' . 'VV[0-9\\/]{3}' . '$/', $metar_raw, $matches)) {

    // VV is the vertical visibility, this should be shown as overcast.
    // If no information is available, VV/// will be used.
    $metar->sky_condition_order[] = 4;
    $metar->sky_condition_text[] = 'overcast';
  }
  if (isset($metar->sky_condition_order)) {
    if (isset($metar->current_sky_condition_order)) {
      foreach ($metar->sky_condition_order as $index => $order) {
        if ($order > $metar->current_sky_condition_order) {
          $metar->current_sky_condition_order = $order;
          $metar->sky_condition = $metar->sky_condition_text[$index];
        }
      }
    }
    else {
      $metar->current_sky_condition_order = $metar->sky_condition_order[0];
      $metar->sky_condition = $metar->sky_condition_text[0];
    }
  }
}