LAKE COUNTY — Experts predict a weak to moderate El Ni?o this winter and into spring, which doesn”t necessarily translate to more or less rain for Northern California.
According to the National Centers for Environmental Prediction”s (NCEP) Climate Prediction Center, El Ni?o represents the warm phase of the El Ni?o/Southern Oscillation (ENSO) cycle.
AccuWeather Senior Meteorologist Brian Wimer explained that what makes an El Nino is above-normal sea surface temperatures near the Equator in the Pacific Ocean. So far, he said, “indications are that there will be at least a weak to moderate El Ni?o this winter.”
However, the waters are muddy regarding what that means for Northern California. “That is not a good indicator that it will be wetter than normal or drier than normal winter in Northern California,” said Wimer.
What happens typically during an El Ni?o, explained Wimer, is that storms are pushed farther south from Washington and Oregon. This normally creates wetter conditions in Southern California, but whether or not that translates to Northern California is anybody”s guess.
NCEP says El Ni?o”s effects include “warmer-than-average temperatures … over the western and northern United States.”
That, according to Meteorologist Cindy Palmer of the National Weather Service”s Sacramento office, does not necessarily include the Bay Area. She clarified that, at this point, no prediction can be made about the amount of rain Northern California will get this winter and spring, or about the temperature being warmer or colder than average.
Everybody clear on that?
Palmer explained that while El Ni?o has been traditionally blamed for unusual weather, it is not accurate to blame it this time, or in general, concerning Northern California. “There”s not enough of a correlation, unless it”s a strong enough El Ni?o, to predict precipitation,” she explained.
Palmer noted that when looking at precipitation data for previous years in which the area has experienced a mild to moderate El Ni?o, there is no line of demarcation for rainfall.
“For Northern California it can go either way, because sometimes we can get enhancement off of the southern jet, and sometimes we can get enhancement off of the northern jet,” said Palmer. “We can get storms coming out of the Pacific Northwest (meaning Oregon and Washington) or subtropical moisture coming north. Sometimes we get sandwiched between the two, and we stay dry.”
As for an indication of how warm our winter may be, Palmer again explained that NorCal can go either way. “There”s more of a trend where temperatures could be above average, but not necessarily,” she said.
Whatever its effect on the Bay Area, El Ni?o is nonetheless an imminent reality.
The latest ENSO diagnostic discussion, released Thursday, elaborated on the indications of an upcoming El Ni?o season. They include warmer eastern and central Pacific temperatures than are normal, weaker-than-normal easterly winds across the Pacific and anomalies on the Southern Oscillation Index (SOI), which points to a pressure change that is a tell-tale sign of an oncoming El Ni?o.
Conditions are predicted to last through the end of the year and into next spring, said the ENSO discussion.
Nationwide, the effects of this year”s El Ni?o will possibly give Gulf Coast and Florida a bit of a soaking, while drying out the Ohio Valley and the Pacific Northwest.
Globally, Most of Malaysia, Indonesia, some tropical North Pacific islands, northern South America and southeastern Africa can expect to drier-than-average conditions. Meanwhile, East Africa, Uruguay, northeastern Argentina, southern Brazil and the coasts of Ecuador and northern Peru can expect more rain than usual.
While we can reasonably expect more rain locally, said Palmer, she held that it won”t necessarily be more than average. This first storm of the season was brought on by a low pressure system higher in the atmosphere, which is expected to head south and to the east, allowing higher pressure to build in the area, Palmer predicted.
“By this weekend,” said Palmer, “we”ll be looking at dry and warmer conditions prevailing with temps in the Lakeport area in the mid to upper 70s.”
When asked if we can expect an early winter, Palmer said that “right now we”re still in the transition season and we”re seeing dry and warmer weather.”
The weather, as usual, will do what it will.
Contact Tiffany Revelle at trevelle@record-bee.com.
