The U.S. National Hurricane Center says two tropical storms have gathered strength off Mexico’s Pacific coast Monday, with one forecast to become a hurricane later in the day.

National Hurricane Center forecasters on June 8 said tropical activity in the Atlantic, Caribbean or Gulf of America is unlikely for now.

Barbara was a tropical storm in the North Pacific Ocean early Monday Mountain time, the National Hurricane Center said in its latest advisory. The tropical storm had sustained wind speeds of 70 miles per hour.