[Chuck Kennedy]

There's no rule against using some method to determine the wind direction and strength. Far as I know, you could carry a portable weather station with wind vane and anemometer. The only restriction in the rules is seeing what the affect of the wind might be by making practice throws.

In theory, you could be penalized for "damaging foliage" by pulling up live grass to test the wind and even moreso if you pick up grass or anything else that's unattached like pine needles in front of your lie. Perhaps a good choice would be to carry your own container of ...ahem, dried grass you could toss in the air to test the wind. Seems like that's been a tradition by many over the years, other than the "tossing in the air" part. Towel is fine.