Bradycardia can be caused by: 1  Changes in the heart that are the result of aging.  Diseases that damage the heart's electrical system. These include coronary artery disease, heart attack, and infections such as endocarditis and myocarditis.
Portland Weather In May. The highest recorded temperature in May for Portland for the past 70 years was 100 degrees Fahrenheit, most recently measured on May 28, 1983, and the normal high is 67.
However, nowhere on the northern Oregon coast is significantly warmer than any other place there. During August, when the inland valleys are scorching, the coast is foggy and cool ~60-65 degrees. The hottest days on the Oregon coast are during September and Indian Summer when it can be 75-80. Source(s): BTDT.