"Smells may range from fruity/flowery to sharp/pungent, garlic/horseradish-like, bitter almonds, peach kernels and new-mown grass/hay," according to the FBI advisory.
That's not quite right. If you can smell the stuff, you're clearly ALREADY downwind of it and if you try to walk upwind of it directly, you'll be walking THROUGH it. The best plan would be to run, not walk, directly orthoganal to the direction of the wind until you CAN'T smell it, and then try to get upwind.