Removing this effect

http://www.kirupa.com/developer/mx/snow2.htm

So, I incorporated the effect shown in this tutorial into a project thing I’m working on. It’s working fine but I’ve noticed that it plays on all of my frames. I only want it on the one frame. Is there possibly an additional line(s) of code I can add to make it only appear on the one frame? I’ve tried to go to the other frames and add a removeMovieClip() but it didn’t work. I’m not new to Flash persay, but I haven’t used it in about 3 years, so my previous skills have regressed as well as general know-how. I’m just slowly picking back up on the basics, and intermediate things. To be honest, coding wasn’t ever really my strong suit. So, if there’s a better way I could be going about this, please let me know.

Code on the movie clip:
onClipEvent (load) {
//specifies the size of the movie stage
movieWidth = 300;
movieHeight = 200;

//variables that will modify the falling snow
i = 1+Math.random()*2;
k = -Math.PI+Math.random()*Math.PI;

//giving each snowflake unique characteristics
this._xscale = this._yscale=50+Math.random()*100;
this._alpha = 75+Math.random()*100;
this._x = -10+Math.random()*movieWidth;
this._y = -10+Math.random()*movieHeight;

}
onClipEvent (enterFrame) {
//putting it all together
rad += (k/180)*Math.PI;
this._x -= Math.cos(rad);
this._y += i;
if (this._y>=movieHeight) {
this._y = -5;
}
if ((this._x>=movieWidth) || (this._x<=0)) {
this._x = -10+Math.random()*movieWidth;
this._y = -5;
}
}

Code on the first frame:
for (k=0; k<50; k++) {
duplicateMovieClip(this.snow, “snow”+k, k);
}