[keep'mcool]

Last summer I nearly lost my truck at the ramp when I launched; in my case it wasn't that it was pulled in by the weight of boat (it was already floating) but rather that there is no traction to be found when that green stuff is wet. My wheel chocks (two of them) slid on that stuff along with the truck, I had to retrieve them from the water when the spectacle was over. My preference is to neither launch nor retrieve at low tide but since that isn't an option for you, here's my advice:

Find a dry spot, that shouldn't be an issue on a Thursday but if it has been busy and a dry spot isn't available, take a pass.

If you have 4 wheel drive, engage it.

Leave the truck running and the driver's door open in case you have to bail.

Chock all the tires, your front tires shouldn't be on the green stuff so the chocks will grab. That extra help may be what keep you out of the water(the sand suggestion sounds like a real good one).

Pull the plug if the truck slips at all. This is where I went wrong; the instant I put my truck in park it slipped about 2 inches and then stopped. I figured the chocks would keep me in place once I set them. WRONG!!!

Helplessly standing at the back of my truck as the waters of the Atlantic engulfed it was a sucky feeling. The only thing that kept me from losing it was getting in and driving it away, at that point the bed was already half filled with water.

Good luck!!!

p.s. the following week when I launched I was introduced to a guy whose jeep had been totally pulled in earlier that that day. His dog used the back window to get out and swim to safety.