Forecasters say Tropical Storm Jova is expected to become a hurricane sometime in the next day or so over the eastern Pacific Ocean.
Earlier Friday, Irwin strengthened to become the eighth hurricane of the eastern Pacific season.
Late Friday morning, both storms remained far from land off the coast of Mexico.
Irwin was moving west-northwest at about 8 mph (13 kph), but current models show the storm could take a turn back toward the east and move toward land. Jova was moving northwest at about 8 mph (13 kph). Models show it also could take a turn toward the northeast and possibly make landfall sometime next week over Mexico.
In the Atlantic, Hurricane Philippe was far off the U.S. coast and was not expected to threaten land.
Explore further: Global warming 'pause' since 1998 reflects natural fluctuation, study concludes