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There are no highly accurate guides to winter in August

We like Slate. Their pieces are innovative, their writing is professional, and their staff is talented. The research they conduct is often top-notch, and their social media presence is impressive.

We don’t like the piece they published earlier today. Neither should any meteorologist, professional forecaster, hobbyist, or reader, for that matter. The article,  A Very Early Yet Highly Accurate Guide to This Coming Winter is already irresponsible in its title. The piece goes on to elaborate on the fact that, due to the increasing confidence of an El Nino, forecasters can see what’s coming this upcoming winter with high confidence. From California to the Pacific Northwest and Urban Northeast, the article proclaims that the forecast certainty is higher than ever. Not surprisingly, it also calls for snowier than normal conditions here in the Northeast.

Let’s make something very clear: There are no highly accurate guides to the upcoming winter issued in August. It’s meteorologically irresponsible to claim anything as such. Seasonal forecasting is, inherently, uncertain at this range. Meteorologists, trade forecasters, and long range experts know that now more than ever, projecting that uncertainty and explaining the reasoning behind it is the best option. Making a near-guarantee statement at a four month range, is not.

The methodology behind the forecast can use some tweaking as well. The article’s author states that he used the following method to come up with a “Highly Accurate Guide” to the upcoming winter, which we’d like to remind you again, is four months away.

To make the above predictions, I took a blend of the most recent North American Multi-Model Ensemble, my go-to source for seasonal forecast information, and a blend of the large-scale weather during four past El Niños that I think are particularly close fits with the current one. Those four El Niños are: 1957–58, 1986–87, 1987–88, and 1997–98.

To simplify things, the author used four analog years and one long range weather model to produce this forecast. May we remind you again that winter is four months away?

El Nino is, in fact, strengthening. The weekly sea surface temperature anomalies confirm that.

El Nino is, in fact, strengthening. The weekly sea surface temperature anomalies confirm that.

Let’s take a step back. Here’s what we know at this point: 

El Nino is, in fact, strengthening. We published an article on it’s strength and forecast for continued strengthening a little over a month ago. 

Forecast models are currently suggesting that a very “El-Nino-esq” pattern will begin to take over by the middle of Autumn. They aren’t, however, consistent with the impacts it will have on the United States, especially the Northeast.

Here are potential caveats to the forecast moving forward:

We are, admittedly, reaching the stage of time in the year where it becomes important to monitor global features, to begin piecing together ideas for the Autumn and Winter ahead. There are some very important players to monitor over the next several weeks. These include, but are not limited to:

  • The exact strength of the El Nino, and it’s positioning and behavior. East-based El Nino’s behave differently than West-Based, etc. These are very important trends to monitor. The exact type of strengthening associated with the event is also important — there are different analog years for each type of behavior.
  • The ocean waters in the Pacific and associated indexes. The Pacific/North American Oscillation and Pacific Decadal Oscillation both have major impacts on the Winter Forecast.
  • The ocean waters off Greenland in the North Atlantic. The North Atlantic Oscillation (NAO) is a huge player in the winters in much of the Continental United States. Analog years can slowly be developed over time while we monitor ocean temperatures and positioning over the North Atlantic and Greenland through October.
  • Blocking/Long Range Modeling: High latitude blocking is a huge — tremendous — player in the overall atmospheric evolution during winter. A large high latitude block can displace cold air and produce snowy conditions over the United States even during the most unfavorable ENSO patterns. Monitoring trends on long range guidance over the next several weeks will be very important.

The bottom line is this: There are no highly accurate guides to winter in August. Forecasters and meteorologists will be continually monitoring trends and patterns over the next several weeks to begin to piece together the puzzle of the winter — and start to formulate ideas as to exactly how the pattern will behave.

You can cancel that order for a high powered snowblower, for now.

You can view our 2014-2015 Winter Forecast, for reference, right here. 

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