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El Nino

Posted: Sat Sep 05, 2015 2:20 pm
by gdurkee
To the extent that meteorologists can predict anything, it's shaping up to be a wet El Nino in California. Overall, most El Nino's don't necessarily correlate with a wet winter, but those that do are strong ones. This year's is shaping up to be one of the strongest on record. Also warm, so a higher snow level. In addition, the Pacific water & atmospheric conditions that may have caused the last 4 years of drought appear to be decaying, giving even more hope for rain.

There's a pretty good monthly blog posted here:

It's pretty technical but the last few paragraphs sum it up well.

Incidentally, investigating on another subject, I ran across some rain statistics for the great flood of 1861-62. There was 110 inches of rain in Sonora in a month or so; and, I think, 132 inches in LA. Sacramento (Old Sacramento --- the reason they moved it) was totally underwater and you could navigate a boat from Tulare Lake all the way to the SF Bay. It was not thought to be an El Nino year.

Re: El Nino

Posted: Sun Sep 06, 2015 8:01 pm
by cefire
Good find! You might be interested in this as well: ... -does.html

I've been hearing meteorology folks who are really cautious that an El Nino will improve drought conditions much. Temprorarily increase reservoirs? Yes. But it sounds like if the winter is warm (which is the EN tendency), snow packs might still be thin.

Here's hoping for a true anomoly: Heavy precip and low snow lines \:D/

Re: El Nino

Posted: Sun Sep 06, 2015 8:04 pm
by cefire
also, the terms they use are just darn fun:

Ridiculously Resilient Ridge
"The Blob"


Re: El Nino

Posted: Sun Sep 06, 2015 8:10 pm
by gdurkee
Ridiculously Resilient Ridge & The Blob -- isn't meteorology great?! Note that your link is from June and the one I posted from last week. The two authors essentially agreed in June but new data indicates a much stronger El Nino. If our future (California and West) is now going to be warmer winters with less snow, water storage strategies will have to change. Many dams (as I understand it) are designed for spring/summer snow runoff and to release much winter precip so as to be ready for flood events. That strategy may no longer work but, of course, they still have to be ready for the huge atmospheric rivers and associated flooding that occur in winter. I don't know anywhere near enough about it as to how DWR and other water agencies will juggle these competing strategies.

Even a snow line above 8,500 would be a major improvement... .


Re: El Nino

Posted: Tue Sep 08, 2015 4:14 pm
by cefire
Yep, that was from his blog several months ago - but his interpretation of what predictions we might make about a strong El Nino should still hold. With time, it appears more and more likely that we'll get a strong one :unibrow:

Re: El Nino

Posted: Tue Sep 08, 2015 11:30 pm
by longri
cefire wrote:...interpretation of what predictions we might make...
Is it possible to legally place bets on the outcome of the Big 2015/16 El NiƱo Event?

I don't think these guys (Swain, Allegretto, the NOAA crew) really know what's going to happen anymore than the guys who write about football or horse racing. I do want to see snow. I really want to see it snow big. But I would love to be able to place a bet that it will be another drought year. As a hedge. With all the wishful thinking I'll bet I could get good odds.

Re: El Nino

Posted: Wed Sep 09, 2015 11:05 am
by Eiprahs
IMOP Longri is on the right path. A strong El Nino does not guarantee a wet California. The probability that the jet stream will steer rain further south than normal is higher, but this does not mean that drought relief is eminent or certain for California. Maybe most of the rain goes into Oregon or Mexico!!

The following may be of interest:

and for the NOAA word on ENSO, check here: ... ts-web.pdf

ENSO is a global pattern. On a global scale, California is not very large.

Also, our predictive models assume that the future will resemble the past. When current conditions mirror a past set of conditions, we expect that what follows near term will be similar to what happened after the past set of conditions. The continuity hypothesis.

Of concern is the area of sea surface showing much greater temperature departures than normal is much larger than in the past. What happens when much or all of the sea surface departs significantly from the past? Is it possible that global air and sea currents can abruptly change--in other words can continuity break down, impairing our predictive models?

Arguably the severe European winters of the past two years can be linked to increased melt water from the arctic covering the northern reaches of the gulf stream, suppressing the gulf stream's warming effect on Europe. So yes, the possibility of an abrupt paradigm shift in global heat transfer exists, and the argument is about how likely an abrupt shift is, not whether it can occur. But that's abstract and doesn't make for 'news you can use'.

So a wet California this winter is by no means certain. I'm hoping, but not betting on it.

Re: El Nino

Posted: Wed Sep 09, 2015 11:10 am
by cefire
Totally agree longri, these folks attempt to predict an incredibly complex dynamical system. Although, meteorology folks do recognize this inherent challenge and qualify their predictions with probabilistic estimates. It is the media who usually misinterprets these predictions as "it's going to happen" rather than "if the model is adequate, it is more likely than usual that this will happen".

An interesting article on our human limitations in understanding probability and weather:

I should also note that there is near consensus that no matter what this season brings, we'll still be in significant or extreme drought :angry:

Re: El Nino

Posted: Fri Sep 11, 2015 12:23 pm
by SSSdave
cefire wrote:...I should also note that there is near consensus that no matter what this season brings, we'll still be in significant or extreme drought :angry:
Actually with major El Nino rains, like I've seen in the strongest winters as 82 or 97, the drought would end, reservoirs would fill, underground aquifers fill, The spring will be epicly green and flowery. Those parroting the "it will take several El Ninos" to get out of the drought either are emigrants that have not lived in the state long, have short memories, or are doing or being coerced to say so for political reasons. The powers of government don't want lots of people to reduce conservation simply from probable forecasts so are no doubt pressuring media not to plant wrong messages in minds of clueless.

Thousands of new homes developers stupidly recently built in valley flood plains like near Latrop will flood, homes built on unstable hillsides will mudslide down hills, and many old farm levees will flood especially in the Delta. There will be all manner of ignorant people owning those lands and homes running to their lawyers to sue the state for not protecting them. Politicians will cry to the federal government. Backdoor politicians will agree it is better to make all we peons in society with our heads in the sand pay for flood damage via the federal programs than developers. Greedy in corps selling the homes will retire to Palm Springs and Miami to play golf while the rest of us get soaked but not from water.

Re: El Nino

Posted: Fri Sep 11, 2015 3:39 pm
by freestone
Thousands of new homes developers stupidly recently built in valley flood plains
Too bad for the homeowners. Homes built on historic and recent flood plains have very expensive Home Owners Insurance premiums.

Also interesting to note is that the sea surface temperature off the California Coast continues to be very warm, just like last year, and some weather forecasters suggested that this contributed to the record dry year.