Map from the Watts Up With That blog shows the warm "blob" in the Pacific Ocean last year. |
El Nino is certainly a prime suspect. Climate change probably plays a bit of a supporting role.
Something else might be at play as well: It's "The Blob." Or more precisely, the fact that the Blob is dying a quick death.
According to the Washington Post, citing weather blogger Cliff Mass, The Blob is, or was, an area of abnormally warm water in the North Pacific, off the coast of the United States and Canada and south of Alaska.
The Blob got going in the first place, said Mass, because persistent high pressure areas in the Northeast Pacific Ocean caused light winds. Usually it's stormy there, and those storms stir up waves that draw up cooler water from the depths of the ocean.
It's thought that this blob, which set up shop three years ago or so, altered weather patterns, creating a big bulge to the north in the jet stream near western North America. That steered storms away from the West Coast, contributing to a punishing drought, especially in California.
On the east side of the bulge in the jet stream, the air flow came down from the Northwest, from Canada, into the eastern third of the United States.
This northwest flow waxed and waned, of course, and sometimes disappeared entirely. But it kept coming back as long as The Blob was in the Pacific Ocean.
This winter, The Blob has cooled off to a ghost of its former self. It's gotten stormier this winter in the northeastern Pacific Ocean, so cooler water is upwelling from the depths.
Since the water has gotten cooler, says the Washington Post, it makes that big west coast bump in the jet stream less likely.
That means, together with El Nino, storms can come off the Pacific Ocean and give California some welcome precipitation. That has been happening in California in recent days
Mild Pacific air is also able to head west to east across the nation, shunting some of those cold blasts from Canada away from the United States.
That's not to say it won't get cold. The death of The Blob just means that those traditional winter cold blasts might be less persistent than they were last winter, and the winter before that.
True, here in the Northeast, an Arctic blast started Sunday evening, but temperatures moderated quite a bit in the past day or so. Back to somewhat above normal temperatures, anyway.
And true, there are signs another Arctic blast might come down from Canada at mid-month.
But there's still no definite sign - at least not yet - that a good chunk of the eastern United States is going to have weeks upon weeks of brutally cold, snowy weather from late January through February into March.
We had two years of that in 2014 and 2015, so that's enough.
I suppose we could end up getting another brutally rough late winter, but the death of the blob is one factor that could tip the scales against such an aggressive winter.
A wide variety of factors influence how winter weather goes. It's not all dependent on The Blob. But at least there's hope that we might not freeze quite as much as last winter.
I think it's more brutal to get rain and ice than to be a little colder and get mostly snow. Haven't liked this winter much this far. Not getting any better in the short term either.
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