[Marricio]

Found these:

IsPlayerInArea tutorial by Pghpunkid

Code by Carlton

Код:

stock IsPlayerInLosSantos(playerid) {
  if(IsPlayerInArea(playerid, 2919.469, 93.423, -782.4177, -2837.724)) {
    return 1;
  }
  return 0;
}

stock IsPlayerInSanFierro(playerid) {
  if(IsPlayerInArea(playerid, -1074.365, -2931.147, 1448.057, -1237.855)) {
    return 1;
  }
  return 0;
}

stock IsPlayerInLasVenturas(playerid) {
  if(IsPlayerInArea(playerid, 2954.502, 782.4177, 2931.147, 595.5717)) {
    return 1;
  }
  return 0;
}

Here is a very nice open-source random weather code created by Southclaw

Guide yourself with that, but please give credits accordingly.