Since the National Weather Service has not revised its prediction of a 95 percent chance of an El Niño developing and continuing through next spring, Hill residents should prepare for the likelihood of a very wet winter. The recent rains are nearly double the historic levels through October.
All of the recent indicators rival the 1997-98 winter, when nearly 40 inches of rain fell here.
“The sea surface temperatures departures have steadily increased. These are values which have not been seen since the big 97-98 episode,” said Climate Prediction Center meteorologist Mike Halpert.
NWS San Diego meteorologist Alex Tardy said last week there is a good change of strong El Niño in the fall of 2015.
Besides the warming equatorial waters, which create the El Niño pattern, Tardy noted that there is still a large “blob” of warmer water west of California. This mass “of warm water can enhance storms to higher rain rates,” he added. “El Niño forecast now has strong above-normal precipitation in Southern California.”
But he stressed that more frequent storms are not necessarily stronger nor warmer. This is not a Pineapple Express, meaning warm atmospheric conditions shifting from the mid-Pacific and Hawaii over Southern California.
Nevertheless the latest NWS winter forecast expects above-average temperature from now through February and well-above average chances of precipitation.
Regarding snow, Tardy thinks that snow levels will be moderate. “If these are not artic or very cold storms,” he said. While Halpert simply said that snow predictions were dependent upon “rapidly evolving atmospheric conditions, which can happen even during a mild winter … the frequency, number and intensity of these events cannot be predicted on a seasonal timescale.”
While all weather forecasters stress that the volume of rain from fall through spring will likely be very high, it will still be insufficient to offset the past four years of drought.
The rainfall levels are already above normal although the El Niño pattern and rain have not yet arrived. Last week, Pine Cove recorded another 0.88 inches of rainfall, for a total of 6.6 inches since the rain year began July 1. The long-term average rain from July through the end of October has been 3.4 inches.
In 2014, Idyllwild recorded about 4.6 inches of rain through the end of October and ended the season with 20 inches, still 6 inches less than the annual average.