Tuesday, August 19, 2014

Perfect-Scoring Winter Analog Paints Ominous Picture for Upcoming Season

For the first time, an analog year has matched all five of my parameters for the upcoming winter season, and is now indicating that the upcoming winter could be another rough one.

ESRL
The analog year that matched all five parameters was the winter of 1958-1959.  The image above shows 500mb height anomalies during the December-January-February period of that winter season. In this graphic, blues and purples depict stormy and cold weather, while yellows and reds indicate warm and quiet weather. The winter of 1958-1959 saw strong ridging/high pressure positioned over the north-central and northwest Pacific regions, with some stormier weather observed near the Gulf of Alaska. This Pacific ridging extended well into the Arctic, helping to dismantle the mid-level polar vortex, sending it to lower latitudes like we saw last winter.
In North America, we observed what appears to be the polar vortex centered in the Canadian Maritimes, spreading its influence across Canada and into the North US. Some slight ridging was recorded in the West US, especially into the Southwest, as well as the Southeast.

Let's push on to the temperature composite for the winter of 1958-1959.

ESRL
During the winter of 1958-1959, much of the nation was locked into a rather brutal winter, with temperature anomalies in the North US dropping below -6.0 degrees Fahrenheit, anomalies not too far off from what we saw this past winter, in 2013-2014. The core of the cold was placed from the Upper Midwest into the Great Lakes, but below-normal temperatures snaked their way through the entirety of the Central and East US, save for Florida, which saw weak ridging. The West US saw a very warm winter in December-January-February of 1958-1959, again a similar story to what was seen in 2013-2014.

Lastly, let's go ahead and check out precipitation anomalies from this analog.

ESRL
During the winter of 1958-1959, very dry conditions plagued the Southern Plains, Gulf Coast, and southern Ohio Valley all the way into the Northeast and Mid-Atlantic regions. Precipitation anomalies below -5.0 inches were recorded in Mississippi, Alabama, Louisiana and Oklahoma, just to name a few. The dry conditions extended north into the Midwest and Upper Midwest, but wetter than average conditions prevailed in the upper Ohio Valley, along the eastern Great Lakes. This was also the scene in Florida, and coastal Texas. The Pacific Northwest experienced a rather wet winter in 1958-1959, while some parts of the Southwest dealt with dry conditions.

Let's break this all down.

The winter of 1958-1959 matched five out of five parameters I set forth that indicate what this winter will look like. For instance, it is expected that the winter of 2014-2015 will see a positive PDO, and the winter of 1958-1959 had that as well. Such a comparison happened, successfully, four other times. It's quite rare to find an analog as similar to projected conditions as this one, and we can only hope that the similarities stick as we head into fall.

Analog forecasting gives us a general idea of what the upcoming winter may be like. It's not a set-in-stone picture of what we will experience. While I cannot confirm that we will see a very dry or cold winter, the chances of both are considered to be elevated, if this analog year is to be believed.

Andrew

10 comments:

Unknown said...

So well written Andrew and so interesting to read what the weather was like for me as a young child in Toledo Ohio!

Anonymous said...

As you do, it is a good idea to put something in your blog like this:
"Analog forecasting gives us a general idea of what the upcoming winter may be like. It's not a set-in-stone picture of what we will experience."

But since people generally do not read an entire article or skim through to find what they want to read, I would suggest putting that kind of message at the top of your blogs so it increases the chances people see it. Just a thought.

roger1868 said...

Andrew, we are in Coatesville, PA. We hope to have a relentless cold winter that will "snow us in". Well, so much for that. (Sometimes I wish we lived in Buffalo, LOL) The last place I would retire to would be FL.,
with its heat and Giant Bugs! We both prefer the frozen North!

Frank-o said...

I really think....This will go bust...when the coming Nino forms, coupled with a NAO....spells snow and cold for the East Coast. I have been watching the wet monsoons in Arizona and this is only one of the signs, that a El-Nino is coming....

Anonymous said...

I thought winter 1958-1959 was a declining el nino not a developing Modoki as you say is happengin this winter. And modoki el ninio winters prove to have more moisture in the southeast through south mid atlantic.

Anonymous said...

Have you seen the August 21 seasonal NOAA predictions ?

Wally Gullang Huntley, Ill. said...

Heard on the radio today that the Old Farmers Almanac is also calling for a colder than normal winter. I didn't see it in their report but the radio was using words like EXTREAM and POLAR VORTEX. But Andrew, I'll go with your forecast.

Anonymous said...

Andrew now that you have a bunch of viewers and stuff you should allow us to interact a bit :D. It's kinda impossible to have conversations with people on here because we have to wait for our comments to be approved...

Frank-o said...

I have been following NOAA and the NWS and The Climate prediction centers long range out looks and I have been really paying attention to their prognostics discussions and.....Well..... I...Dang It!!! As much as I hate to say this.....Data is now really pointing to a central based Nino, which leaves the South East Dry with quick shots of just plain old cold dry air and a yet another boring winter....and Andrew may just be right on target..........

Peter F. Kane said...

Not all Modoki El Niños have the moisture to produce big blockbuster snowstorms. Weak El Niños do not have much moisture in the Southern Jet Stream, and that will reduce the chance of any possible Nor'Easters for next winter. Typically in a Weak El Niño, in the South, including the Gulf Coast, and West, and the warmth tends to be in these areas. Weak El Niños do not have all the full characteristics of a real El Niño. You will have the same exact characteristics that appeared last winter coming next winter. The characteristics I am talking about is the Californian Drought, the Midweest Coolness, and the Florida Ridge. The Mid-Atlantic will have less snow than last year while the Midwest will have above normal snowfall for a second straight year. However it will not be as snowy as last winter. The worst of the cold and snow will be situated in New England and Atlantic Canada.