i am trying to read data from an excel file nd save it to a 2d array removing excess data but when i try to use the 2d arrays outside of the function it doesn't work

const xlsxFile = require('read-excel-file/node');
var x = 0

function excel() {
  xlsxFile('./weather-data.xlsx').then((weather) => {
    var weatherLen = weather.length
    while ( x < weatherLen) {
      if(weather[x][1] == null) {
        delete weather[x]
      }
      x++
    }
    console.log(weather)
    weather_data = weather
  })
}
    
excel()