$re = '/<a href=.*?SWEC.*?/a>/m';
$str = '<a href=https://energyplus.net/weather-download/asia_wmo_region_2/IND//IND_Kota.424520_ISHRAE/IND_Kota.424520_ISHRAE.epw>Download Weather File</a>
<a href=https://energyplus.net/weather-download/europe_wmo_region_6/ESP//ESP_Alicante.083600_SWEC/ESP_Alicante.083600_SWEC.epw>Download Weather File</a>';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php