MONTHLY VARIATION OF PRECIPITATION ECHO OCCURRANCES ACCROSS THE UNITED STATES

Abstract

The U.S. Weather Bureau's network of weather radar stations provides a source of hourly data which indicate the presence or absence of detectable precipitation in the atmosphere within range of the radar. This paper is concerned with variations of precipitation echo occurrences as reported on hourly RAREPS by six WSR-57 radars along a line running from New York City to Sacramento, Calif. When monthly percentage frequencies of precipitation echo occurrrences were computed for each station and compared to variations of precipitation amount, it was evident that the influence of major topographic features may be detected. In addition, in the winter months, an indication of a station's relative continentality may be observed.