Complex sentence: A report of winds, 1010.5 mbar, and heavy thundershowers that were generating high swells was received from a Coast Guard cutter called the "Androscoggin" while the ship was south of Tehuantepec in a northward bend in the ITCZ that was moving westward.
Split into simpler sentences: A report of winds, a barometric pressure of 1010.5 mbar, and heavy thundershowers was received from a Coast Guard cutter called the "Androscoggin" while the ship was south of Tehuantepec. The conditions had developed in a northward bend in the ITCZ that was moving westward.