Monday, August 17, 2015

El Nino Putting Progosticators Into A (Probably Wrong) Winter Forecast Tizzy

A looming El Nino might, maybe, bring welcome
rain to California this winter, but could also
bring severe storms that cause mudslides
like this one during the 1997 El Nino.  
There's been TONS of hype this week over what El Nino will do to the winter weather in our Great Nation.

First of all, it's August. Should we really be looking forward to winter that much?

Also, I've said it before and I'll say it again. Long range forecasts are often wrong. So take anything you hear about this coming winter's weather with a Mack truck sized grain of salt.

First of all, let's update ourselves on El Nino. It's a periodic warming of the eastern Pacific Ocean that disrupts weather world wide.

That's especially true if a particular El Nino is strong. This one is shaping up to be a doozy, possible the strongest on record or close to it.

They're calling the current building pattern the "Godzilla El Nino."

There is some basis for some of the winter forecasts inspired by this strong El Nino. More often than not, El Ninos cause wet winters in California and in the southern tier of the United States. Less reliably, but still quite often, an El Nino will cause a mild winter in the northern Tier of the United States.

So, that means California's drought is going to end, us New Englanders aren't going to shiver to death as we're buried under feet of snow like last year, and the South will have plenty of water for next spring's crops, right?

Not so fast. All kinds of other factors can influence the winter weather. El Nino is not the final arbiter.

The winter forecast is most crucial for California, which is still being crushed by an epic four-year drought.  If El Nino brings those heavy winter rains to the Golden State, happy days will be here again, right?

Well, not totally. Even if the rains materialize, the drought is so deep that it might not be fully erased by a wet winter.

El Ninos also often make California warmer than average. If that happens during the winter, more of the precipitation would fall as rain, not snow in the high Sierra Nevada mountains.

That would be bad, because you want a lot of snow in the California mountains to gradually melt in the spring and summer to feed rivers that supply water to lowland communities.

El Nino rains in California might also come in the form of torrential downpours. Any rain would help of course, but torrential rains would also lead to flash floods, which are obviously bad for people and property caught up in them.

On top of that, maybe the El Nino rains this time might not materialize. Why? Well, there's something called the "Blob" which has been lurking off the west coasts of the United States and Canada for at least a couple years now.

The Blob is an area of unusually warm water that has set up out there. This isn't the same as the hot water associated with El Nino, which is down off the coasts of Central and South America.

The blob of warm water well to the north isn't usually there, especially in an El Nino. This blob could change weather patterns the way it did last year, steering storms away from California and leaving them high and dry again.

This "Blob" also contributed to last year's weather pattern that brought so much snow and cold to the Midwest and Northeast.  Will the Blob attack in the same way this winter? Nobody is sure, and anybody who says they are sure is lying.

There's also the possibility that El Nino could knock out "The Blob" ensuring the hoped for wet California winter. Who knows?

There are other complicated atmospheric and ocean cycles in the Pacific and Atlantic basins which can also screw up those nice, neat El Nino forecasts.

Plus, global warming has screwed up the atmosphere, making things less predictable for any particular location on Earth.

Other outfits are also starting to make their own wacko winter predictions.

The Farmer's Almanac just released its winter forecast, and they insist much of the northern United States, including the Pacific Northwest and New England are in for another bitterly cold and very snowy winter.

That's based on their secret formula for weather predictions. You need a grain of salt bigger than that Mack truck for their forecast, I'm afraid.

Bottom line: I'll tell you in March how the winter weather of 2015-16 turns out.

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