let drops = [];

function setup() {

  createCanvas(windowWidth, windowHeight);

}

​

function draw() {

  background(220);

  for(let i = 0; i < 10; ++i) {

    drops.push([random(width), 0, random(1,5)]);

  }

  for(let el in drops) {

    stroke(120, 0, 120, drops[el][2]*50)

    strokeWeight(drops[el][2]/2.5);

    drops[el][1] += drops[el][2];

    line(drops[el][0], drops[el][1], drops[el][0], drops[el][1] + drops[el][2]*3);

  }

}