There is a... natural explanation for how a temporary path across the Red Sea could have been revealed. It involves the tide, a natural phenomenon that would have fit nicely into a well-thought-out plan by Moses, because Moses would have been able to predict when it would happen.
In certain places in the world, the tide can leave the sea bottom dry for hours and then come roaring back. In fact, in 1798, Napoleon Bonaparte and a small group of soldiers on horseback were crossing the Gulf of Suez, the northern end of the Red Sea, roughly where Moses and the Israelites are said to have crossed. On a mile-long expanse of dry sea bottom exposed at low water, the tide suddenly rushed in, almost drowning them.
The entire article written by Dr. Bruce Parker can be found here. He is the former chief scientist of NOAA's National Ocean Service and is currently a visiting professor at the Stevens Institute of Technology. He is the author of “The Power of the Sea: Tsunamis, Storm Surges, Rogue Waves, and Our Quest to Predict Disasters.”