National Weather Service United States Department of Commerce

Heavy Rain and Flash Flooding Concerns in California; Heavy Snow in the Sierra

An atmospheric river will bring heavy rainfall to lower elevations of California this week, and heavy snow to the Sierra Nevada mountains. Flash flooding, some of which may be locally considerable, will be a concern on the western foothills of the Sierra Nevada mountains through Tuesday. Landslides, rockfalls and mudslides are possible in the Southern California mountains. Read More >

The National Weather Service Cooperative Observer Program (COOP) is a network of over 11,000 volunteer observers across the nation. The NWS in Santa Teresa currently maintains around 30 COOP sites (see fig. 1). The National Weather Service (NWS) will design and set up the site and install the equipment. The NWS also trains the observer to utilize the equipment in taking the observations and to do simple maintenance; otherwise the NWS provides the significant repair and maintenance. These observations are helpful, both for short term forecasts and maintaining a climate base to help track long term trends in the climate.

The great majority of observers take their observations at or near their residence, although a few businesses or government agencies also take observations. These observers take one observation each day of the year, usually either at 0800 or 1800 local time. The observation can be as simple as recorded rainfall, or more often reported, max/min temperatures, rainfall, snowfall and snow depth.  A few sites with agricultural interests even report evaporation and soil temperature. In the past, observers filled out a paper form and sent the form end at the end of each month. Today, many observers transmit their observations electronically via telephone or computer.

 

For more information on the NWS COOP program, visit the NWS COOP page.