Complex sentence: By 2100 UTC on May 24, the existing portions of the warnings between Cabo Corrientes and Manzanillo were upgraded to a hurricane warning, and another tropical storm watch was issued northward to San Blas.
Split into simpler sentences: By 2100 UTC on May 24, the existing portions of the warnings between Cabo Corrientes and Manzanillo was upgraded to a hurricane warning. Additionally, another tropical storm watch was issued from Cabo Corrientes northward to San Blas.