High-pressure ridge back in area
It will divert storms that might have brought rain
Following the coinage of Stanford University scientist Daniel Swain, weather watchers call it the “Ridiculously Resilient Ridge,” sometimes shortened to “Triple R” or “RRR.”
And once again, this stubborn and massive blob of atmospheric high pressure — the culprit in some of our driest recent years — is double-parked above the northeastern Pacific Ocean.
Since it’s a ridge and not, say, a Terribly Tenacious Trough, California and much of the West is enjoying warm and dry days even as we tiptoe to the precipice of winter. And, says meteorologist Jan Null with Golden Gate Weather Services, we can expect to see the RRR stick around for at least a week and a half.
From our chat with Null, here are some things to know about this very dry subject:
Q So what’s with this stubborn ridge?
A We have ridges of high pressure and troughs of low pressure all the time all over the world.
Q How do these meteorological forces shape our weather? A Ridges and troughs help define the jet stream, or storm tracks. Normally, you have a progression of the two that looks like a sine wave; when it’s moving along in the middle latitudes, which is where we are in California, you’ll move between a trough, which gives us rain, and a ridge, which gives us dry weather.
Q So what’s going on now with this Triple R?
A They normally move across the world, but sometimes a pattern gets locked into a certain area for an extended period of time, which is what’s happening now with this ridge. It’s moving north over California and the Northwest, causing higher-than-normal temperatures for this time of year and dry conditions.
Q Why does this happen?
A All around the globe you have this exchange of heat from the Equator with cold air fromthe Arctic region and that makes these patterns move along, but sometimes everything comes into balance and the weather patterns don’t move around as they normally do.
Q So we have a sort of meteorological standoff going on?
A That’s right. We’re paused for now. So we’ll have mostly dry conditions in the central and southern parts of the Bay Area for the next ten days or so. There will be some weak systems bumping up against that ridge that may bring some light rain to the North Bay, but nothing really memorable.
Q Does this mean we’re in for another record drought? A No. What’s going on now doesn’t mean anything for the rest of the season. I hear people saying ‘ We’re going back into a drought,’ but this is a short- term, temporary thing we’re seeing right now. If we’re still talking about this ridge in April, then we can talk drought.