Many rip currents are temporary, while others are permanent. Most trouble spots are less than 30 feet wide. Often they occur after storms. A difference in water color murkier from sediments or darker because of greater depths. A difference in waves.
Rip currents have larger, choppier waves, with calmer ones near shore.
Foam or objects moving steadily seaward. An offshore plume of turbid water past the sandbars. If you cannot swim across the rip current, float calmly until it dissipates, usually just beyond the breakers then swim diagonally to shore. If you cannot swim, stay in wading depths close to shore. The Sea Grant brochure is now being reprinted.