Saturday, October 11, 2014

Wimpy El Nino

We are now close enough to the winter season to have a fairly clear idea of the El Nino situation ahead.  Remember that El Ninos are associated with warmer than normal water in the tropical Pacific and that such anomalies can influence Northwest weather (less storms, warmer, less snow).

Originally there was a lot of talk (last spring) of the potential for a Super El Nino, with some of the global warming "advocate" sites talking about its effects on the global temperature record (global temperatures can warm substantially with strong El Ninos).

However, the sea surface temperatures in the critical  central Pacific is only modestly warmer than normal and the atmospheric circulation has not reacted in a way to reinforce the warming and push us towards a moderate or stronger El Nino.

Let's start with one of the key measures:  the sea surface temperature in the Nino 3.4 area of the tropical Pacific.  The official definition of El Nino is an anomaly  there greater than .5C.  We are not there now and in fact the SST has declined recently.

A number of groups run statistical and full-physics models to simulate El Nino.  They suggest we will have an El Nino, but a weak one.  However, verifying these models for the forecasts started earlier in the year, suggest they have been pushing warming in an unrealistic way.

The National Weather Service Climate Forecast System (CFS) model is now going for an entirely marginal event, barely reaching the .5C criterion

And the official probabilities for El Nino are now only about 65%.

So we should not expect much more than a marginal El Nino during the upcoming fall and early winter months.  And amplitude matters.   Weak El Ninos have lesser impacts.

The correlation of our weather with El Nino is not perfect to start with.  And for weak El Nino years the relationship weakens further.

Let me illustrate this for you.

Here are the precipitation patterns across the U.S. for some STRONG El Nino years.  The most consistent implication is  the wetter southeast U.S.   There is a tendency for southern/central California to be wetter.  The Northwest is less consistent.

But for weak El Nino years, the precipitation patterns are all over the place.  I would not place bets on anything.  This is the story of our upcoming winter unless El Nino revs up unexpectedly.

So based on the correlation with El Nino, we have very little guidance for the upcoming winter. Sorry.

The latest NWS Climate Forecast System forecasts for December-January-February is for warmer than average over much of the U.S.  No hint of the feared "polar vortex."
What about precipitation?  Very little signal over the Northwest.  But wow...California is much wetter than normal.  This would really help the drought.  Fingers crossed.

And this week should be a shock to some.  Showers today.  Generally dry on Sunday and Monday day.  But they the celestial spigots will turn on.

Hopefully, the rain will be over by next Saturday.  Why?   Because one of my favorite events will occur Sunday morning at 9AM:  the UW Dawg Dash fun run.  For more information, check out their site:


Weatherfreak said...

Really wish we could either have a strong El Nino or strong La Nina, since we would have better idea for our winter. The weak events are like playing craps! I've been telling my friends and family to expect warmer and drier. I am sure I will be mocked come April... ;) One factor that will be interesting to watch is the much warmer water in the Gulf of AK. Will that produce stronger storms, (warm water, more moisture to work with) or higher pressure resulting in a more tranquil pattern. Maybe a combo of both??? As always, hoping we locked in a strong Northerly pattern come about Dec. 26th lasting a couple weeks. 68/69' has got to repeat at some point! ;)

Skokomish said...

Holy tornado warning! I've never actually seen the emergency broadcast system in action for anything other than a test. AND THIS WAS NOT A TEST,

Lowell Skoog said...

Cliff, can you comment on the tornado warning for Pierce County that was broadcast today (10/11) around 12:30 pm? I was listening to KPLU and the alert cut in over regular programming. The warning was so uncharacteristic for this region that for a moment I thought it was a prank. So I switched to the NOAA weather radio in my car and heard the alert there too. It was only played once. (I hoped to record it on my smartphone to play for my disbelieving friends.)

Jack Bloss said...

I'm sure Cliff can give a better explanation of what happened but apparently there was a waterspout over the sound that triggered a tornado warning. No damage occurred as it did not reach land but it lasted about 2 minutes and it's quite impressive for this area, especially this time of year. Look it up online and you can see some pictures and videos. Pretty cool.

caveat emptor said...

Good chance of a new record temp even with a wimpy el nino

Placeholder said...

This is quite the nightmare scenario for the climate change alarmists.

Here we are, in the 19th consecutive year of the "hiatus" in global warming. The "hiatus" has already invalidated the IPCC's climate models, yet the usual crew had been hoping to be able to blur that reality with an El Nino-driven temperature increase that broke the "hiatus," even if only for one year.

But that's not going to happen, and with the PDO in place, we'll probably have at least a 25-year "hiatus," and maybe longer. The collapse of the climate change establishment is coming.

And if that prediction of a wet winter in CA comes true, talk about yer twisting of the knife! Most of us want the drought to end, but the climate change radicals have been hoping for a disaster. Which, if the forecast comes true, they won't get.

Better find a new trendy cause, and leave the weather to the weathermen.

jno62 said...

Yes, placeholder, nothing has changed.

Tornadoes in October. Just like it's always been. Right?

Placeholder said...

jno62, are you seriously going to try to attribute that tornado to global warming? Pretty desperate, to put it mildly.

Richard said...

Totally agree.