While it may seem like September 4th is a little early to start talking about rainwear, I can assure you it is not. The reason for this particular post on this particular day is the unseasonal rain that doused our Labor Day camping trip and forced an undignified retreat to the car at 5:30 in the am. In retrospect it was poor planning and lack of waterproof protection that kept us from staying dry.
Companies that wait until the first rains of the season before they order their waterproof clothing will likely be in a similar situation. If it hasn't already happened. Trust me when I say that just hoping those first drops you hear are going to be the last is whistling into the wind (and rain). In fact, it could be the beginning of a deluge that brings all thoughts of a leisurely breakfast and a plodding, relaxed breaking down of camp (or whatever your project may be) to a rude, abrupt end. It may be the prelude to a downpour that soaks you like a wet rat and leaves you ruing the day you bought that cheap tent or decided against the seasonal waterproofing session any right-minded camper would employ.
Then again, it may be no big deal. If you are warm and dry, everything looks a bit more manageable. Please, learn from my mistake and take a look at the rain gear you have left over from previous seasons. Figure out what you need to keep the wheels of progress from getting rusty. Don't put it off till you have a bunch of soaked, complaining kids (or employees) sitting in the car (or company truck). Whether you need an inexpensive yellow PVC raincoat, or you want long-term protection with a waterproof reflective jacket, the important thing is to have it handy before the rain is upon you.
Believe me when I say it might be here sooner than you think. It certainly was for me.