Custom Wind Script = random rotation around world.space

unity: wind

using UnityEngine;
using System.Collections;

public class windController : MonoBehaviour {
	
	//TODO
	//1) Inwards / Outwards Direction
	
	float t;
	int direction = 1;			//Direction of rotation the wind object makes
	public static float windForce; 		//Global variable - force of the wind. 
	public float windTimeVar = 5; 		//Time between updates.
	public float minWindForce = 10 ;	//Absolute minimum the windforce can be
	public float maxWindForce = 10 ;	//Absolute maximum the windforce can be
	public float dWindForce = 0.1f; 	//Change in windforce.
	public float forcePickUp;		//Amount of force needed before objects react to wind
	public int directionVariance = 5 ;	// Range of change out of 10
	public bool dynamicMovement = false;
	public string taggedGameObjects;
	//public enum Direction {Away, Towards};
	//public Direction forceDirection;

	//Add Gizmo for the editor.
	void OnDrawGizmos () {
		Gizmos.DrawIcon (transform.position, "icon_wind.png");
	}
	
	//Randomly pick starting values and transforms.
	void  Start (){
		windForce = (int) Random.Range(minWindForce,maxWindForce);
		if (dynamicMovement == true) {
			transform.localRotation = Quaternion.Euler(Random.Range(0, 360), Random.Range(0, 360), Random.Range(0, 360));
		};
	}

	//Randomly adjust values.
	void  Update (){
	  	StartCoroutine(rand());
		if (dynamicMovement == true) {
			transform.RotateAround (new Vector3(0,0,0), new Vector3(0,direction,0), 20 * Time.deltaTime);
		};
		
		//Objects tagged will look in the direction of the wind
		if(windForce >= forcePickUp) {
			if (taggedGameObjects != null) {
				GameObject[] tagged;
	       		tagged = GameObject.FindGameObjectsWithTag(taggedGameObjects);
				foreach (GameObject obj in tagged) {	
					Vector3 relativePos = new Vector3(transform.position.x,obj.transform.position.y,transform.position.z) - obj.transform.position;
			        Quaternion rotation = Quaternion.LookRotation(relativePos);
		  	   		obj.transform.rotation = Quaternion.Slerp(obj.transform.rotation, rotation, Time.deltaTime * 2.0f);
				}
			} else {
				UnityEngine.Debug.Log ("No Tag set, you can however still use the script");
			}
		}
		
		UnityEngine.Debug.Log (windForce);
	}

	//Determine wind force and direction randomly. Update variables accordingly.
	IEnumerator  rand (){
		int rand = Random.Range(1,10);
		if(rand > directionVariance) {
			direction = Random.Range(-1,2);
		}

		//Time before update
		t=Random.Range(windTimeVar,2*windTimeVar);
		
		//Change in windforce variables
		windForce += Random.Range(-dWindForce,dWindForce);
		windForce = Mathf.Clamp(windForce,minWindForce,maxWindForce);

		yield return new WaitForSeconds(t);
	}

}