Atenolol and chlorthalidone combination is used to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly.
San Marcos Average Weather. 1  The highest monthly average temperature in San Marcos for August is 70 degrees. 2  The lowest monthly average temperature in San Marcos for January is 55 degrees. 3  The most monthly precipitation in San Marcos occurs in January with 2.3 inches.  The air quality index in San Marcos is 22% worse than the national average.
San Diego has on average 146 sunny days and 117 partly cloudy days a year. The average annual precipitation is less than 12 inches (300 mm), resulting in a borderline arid climate. Rainfall is strongly concentrated in the cooler half of the year, particularly the months December through March, although precipitation is lower than any other part of the U.S. west coast.