Southern California is roasting in record heat this week — not at all what was expected in mid-February during a “super El Niño.” Where is all the cool weather and drought-busting rain? One climate researcher says that even though this El Niño is among the strongest on record, it lacks important features that influence West Coast weather.
Temperatures are scorching for mid-February, soaring past previous records. Since Monday, 37 warm temperature records have been set in the San Diego and Los Angeles regions.
In Santa Ana, Calif., the mercury rose to 95 degrees on Tuesday afternoon, breaking the record for the date of 86 degrees set in 2012 and tying the all-time warmest temperature ever recorded in the month of February at that location.
At Long Beach, the high climbed to 92 degrees on Tuesday, breaking the old record of 86 set in 1991. It was 91 degrees at Camarillo, besting the previous record of 88 set in 2006, and 90 degrees at UCLA, trumping the 85-degree record that was set in 2006 as well.
Temperatures are expected to moderate a bit by the weekend, but not by much, and the L.A. Marathon is scheduled to start Sunday morning, with the Olympic trials race beginning at 10:06 a.m. and ending at the hottest time of the day. The forecast high for Sunday is 85 degrees — 20 degrees above average for Feb. 14.
Even though organizers scheduled this race a full month before last year’s race, the outcome doesn’t look any better. Last year, more than 30 people were sent to the hospital when the temperature hit 90 degrees at the finish line near the beach, and the marathon medical director is expecting a similar result this year.
High pressure and strong Santa Ana winds are the immediate weather factors behind this week’s unseasonable heat wave. A huge ridge, reminiscent of the ridiculously resilient ridge of last winter, extends north into Alaska this week. Strong offshore winds have been gusting off the mountains to 40, 50 and 60 mph, driving up the temperature even further.
This is certainly not the weather pattern that Southern California was expecting this year, in the midst of a crazy strong Godzilla El Niño. California as a whole was hoping for a cool winter and drought-busting El Niño rain, not dry weather and a record-breaking heat wave.
Kevin Trenberth, a climate change and El Niño expert at the National Center for Atmospheric Research, said that while this is technically a very strong El Niño, it’s not playing out as expected, perhaps because people tend to be too focused on temperatures of specific regions, rather than the big picture.
“This El Niño has been called ‘very strong’ and one of the top-three strongest on record,” said Trenberth. “That is true if one measures it only by the warmth in the eastern tropical Pacific. But most El Niños also feature a cooling in the western tropical Pacific, and that is largely absent this year.”
As a result, Trenberth said, the differences in temperature along the equator are much less than previous super El Niños, and the reversal in the trade winds that blow across the tropics is much weaker than we saw in the winter of 1997-1998, when Southern California saw nearly 14 inches of rain in the month of February alone.
In addition, a lot of action is occurring in a very warm tropical Indian Ocean, which is interfering with the Pacific Ocean activity.
“A consequence of this is that the activity in the eastern Pacific has been nowhere near as strong as expected, and in fact it disappeared a couple of weeks ago,” said Trenberth. It’s the eastern Pacific activity that tends to have the most influence on Southern California storm tracks.
What that means for Southern California going forward is that all bets are off about “typical” El Niño weather patterns, and we may have already seen peak winter rainfall come and go.