Will winter bring cold and snow, warm rain, or some combination of these to the mountains of Southern California? Will the timing of cold and wet air masses moving into the region match up in such a way that snow results?
So what can Southern California expect this coming winter, according to the Lords of Climate at the National Weather Service? Short and sweet: The NWS long-range forecast for the region calls for an equal chance of above-normal, normal, and below-normal precipitation and temperatures.
Elevation is the determinant in snowfall across this region of California, with Los Angeles posting only trace amounts each year, Bishop 8 inches on average, Mountain High Ski Resort 12 feet, and Mammoth Mountain Ski Area, while not in Southern California, gets the predominance of its guests from the city. Mammoth averages 33 feet.
The National Weather Service puts out long-range forecasts for the entire country. These prognostications are based on historic weather patterns, temperature and precipitation records, and other climate indicators from around the globe. They sometimes hit the nail on the head, but often do not.
Some seek counsel elsewhere. Do woolly bear caterpillars have thicker coats than normal? Are there more nuts falling, and are squirrels scampering even more madly than usual to store up winter food? It's a mystery why people ascribe powers of foreknowledge to insects, rodents, and nuts, but some do. After comparing long-range predictions with what actually happens, some conclude the critters and acorns are just as reliable as the scientists.
Jeremy Davis, senior meteorologist with Weather Routing Inc., a weather service in upstate New York, questions the wisdom of over-reliance on long-range forecasts. Davis suggests that the devil in forecasting lies in the little details of timing that determine the shape of the weather.
"Whether you have snow or rain depends on exactly when the precipitation falls," Davis said. "It can be warm and dry, or cold and precipitating. The long-range forecasts missed the cold snap in January, and the rainy June."