Joe’s Weather Blog: A look at El Nino (WED-10/31)
Happy Halloween…I had a feeling over the past weekend that there might be a few sprinkles out there today…and sure enough, about 3 hours after I got the car washed…drove through about 50 raindrops coming into work this afternoon. So it goes…and there are still a few sprinkles in parts of the area although it really won’t affect the ghosts and goblins out there all that much I don’t think.
Weather-wise the main pattern is a changeable one…which is more or less typical especially during November. You can get some very big storms nationwide during this transition time. Daylight gets to become less and less across the northern latitudes and with the continuing warmth of the southern latitudes and the warm ocean waters…the atmosphere can get really fired up. Blizzards (heavy snows)…severe weather…lake effect snows and winds should all should be expected during this month.
Tonight: Cloudy skies with cool but not overly cold temperatures with lows around 40°
Thursday: Overall a pretty nice day with highs 60-65°
Friday: There may be a few showers out there early in the AM. It will be blustery as well with highs in the 50s but overall not too bad of a day.
As November kicks off…a brief look back at October which was about as eventful as one could ask for changeable weather…especially during the 1st 2 weeks of the month…we had the drought>deluge…record cold lows…accumulating snows…fabulous fall colors and in the end…temperatures that we’re slightly below average…by about a degree or so!
Meanwhile the rain was so welcome…the flooding wasn’t be the rain was in many cases helping to fill up the ponds and the lakes nicely with all the runoff. We’ve turned rather dry again and there aren’t any big rain makers coming soon…but at least we had a refill to many low water areas out there. This was the 14th wettest month (of any) in KC too and the 2nd wettest October
It was a month for sure to remember and whether the weather helped (it didn’t hurt for a change) and perhaps the combination of the late leaf out from such a weird springtime start in the region…whatever the reason…so glad that the fall colors are looking as good as their looking.
A lot of folks are asking about the winter forecast which is still about 3 weeks away from being issued…probably sometime Thanksgiving week would be my guess although Michelle will be giving you come clues in a few weeks…it’s still though too early one way or the other to guestimate really. I’ve told you about the “blob” in the northern Pacific Ocean…today let’s go farther south…towards the equator!
Yup…time to talk about El Nino.
El Nino is an warming of the equatorial waters of the Pacific Ocean. We typically break down the equatorial Pacific Ocean into regions. This regions look like this…
Typically when we talk about El Nino…we talk about the combined regions of 3 & 4…commonly called 3.4. This is more out towards the central Pacific Ocean. So what’s going on out there now?
Look towards the Equator…
On the far left side on the image above…look for the number 0…that is the Equator line and then look towards the right all the way towards South America…notice the warmer waters towards the Dateline (180°>-80° on the bottom legend) from west to east. That’s El Nino.
El Nino isn’t exactly uncommon these days…there have been many of them. Their strength is one thing that can be important in thinking about winter weather trends…but NOT all El Ninos are the same.
There are times…as recently as the winter of 2015-16 that El Nino is very strong…very strong El Ninos can overwhelm the atmosphere and create enough feedback that the US is rather warm…
Other El Ninos can be weak to moderate. I think this year we’re going to straddle those categories…high end weak or perhaps low end moderate.
The weather trends get much more murky in these situations…and that’s why, most times I feel it’s crazy to base a forecast off this types of El Ninos. I think the following two graphic shows why.
Note how, given a strong El Nino…you can perhaps statistically leans a forecast to milder conditions. Nothing really pops in terms of confidence with a moderate or weak El Nino. Perhaps maybe some cold signals for the eastern part of the country.
Precip wise..really all over the place. Weak events perhaps tend to look dry for may areas in the eastern Plains region.
I mentioned that all El Ninos are not the same in terms of strength, if you will. There is also a big issue of where the bigger anomalies (from a water temperature standpoint are located. The farther west they are the different the influence is on the weather pattern (if there is one).
Notice that pocket of cooler water averages in near the South American coastline…and also north of Australia…then the middle of the oreo cookie has the strong anomalies…that is a “modiki” El Nino.
Note the average trends for an El Nino modiki
Hmmm for the Plains and eastwards.
For precip there’s this…
Modiki is actually a Japanese word meaning “a similar but different thing”
What years were Modiki events? According to this AMS published paper in 2013 this is what we worked with through 2010. 1914/15, 1923/24, 1940/41, 1941/42, 1963/64, 1968/69, 1977/78, 1979/80, 1987/88, 1990/91, 1991/92, 1992/93, 1993/94, 1994/95, 2002/03, 2004/05, and 2009/10
A future blog will dive deeper into that aspect above…perhaps on Friday. There were some BIG time Plains winters a few of those selected years…as recently as 2009-10 as I’m sure the snowlovers remember. Also see the 1977-78 winter many remember that winter as being particularly brutal! Our second coldest DEC>FEB as a matter of fact in KC! 1978-79 winter was jsut a few tenths of a degree colder.
Again just one of the many things forecasters look at when thinking about a winter forecast.
Our feature photo is from Jay Bailey…stunning!