Tuesday, October 20, 2015

"Do You Know What This Means???"
Scroll below for a video tribute to the movie taking you "Back In Time"

1:20 PM 10/20 - With a whiff of winter across the Mid-Atlantic early this week, thoughts are turning to what is ahead for the upcoming season. In long range forecasting, October is a critical month to monitor and analyze a number of indicators that provide early clues on which large scale influences may affect the winter pattern in any given year.

What's more historically important is the long-awaited arrival of "Back to the Future" day, as projected 30 years ago to be this week: October 21, 2015. We hope you enjoy this first of two installments of our BTTF themed overview. Though this report may initially seem heavy, we are pleased to announce that despite Doc Brown's concerns, the Earth's gravitational pull appears to be in fine shape here in 2015. 

Considering the wild winters of late, perhaps it is little surprise to learn that thanks in part to a strong El Nino underway, the 2015-16 season looks to continue the trend of unique weather patterns that undoubtedly will throw winter weather managers into fits that only Doc could admire!

If you're seeking a short version of what this means, we can say the following about indicators heading toward December 1.
GREAT SCOTT! Latest snowcover is quite sparse in the U.S, and Canada
compared to Autumns that preceded snowy winters. 
  • Slower rebound of northern snow cover as compared to recent years such as 2014, 2013 and 2009 suggests that for the Mid-Atlantic's urbanized corridor east of I-81, we expect a delayed start to significant snow events until mid-December at the earliest.
  • Arctic Sea Ice rebuild from the September lows came in notably less than levels observed in those 3 marker years listed above. (View the final 2015 sea ice graphic from the NOAA National Ice Center.) Although many in the East have felt quite the winter-like chill at present, this current spell is short-lived due to a lack of deep cold in the Arctic as compared to what is usually seen this time of year. 
  • An already record strong El Nino, that "Frenemy" of climate watchers and school students alike, has produced sea surface temperatures in the equatorial East Pacific up to 10 degrees F above normal! Will this lead to more snow days in the East? Only George McFly may know if that lurks in your density, err, destiny. 
  • Accounting for these slow-to-start factors in the long range forecast reveals clues that help answer the question Doc Brown asked in the headline. If the Arctic takes longer than usual to build it's reserve of deep cold, when that finally does occur and gets unleashed south--- yep, you figured it out.
It means we hypothesize the second half of Winter for the Mid-Atlantic and Northeast U.S. could end up similar to 2015 AND 2014, suggesting conditions such as:
  • Significant to extreme cold for January into February, rivaling records in '14 and '15. 
  • Disruptive to crippling storms for February into early March, marked by an El Nino-fueled pattern that delivers copious Pacific moisture, creating high precip events. 
  • Prolonged periods of below normal cold into March, impacting the start of Spring sports much like what was seen in March 2003, 2010 and 2015.
A usual suspect expected to play a big role again this season is the North Atlantic Oscillation, which under the right arrangement, can initiate the most unwelcome "Cross Polar Flow" and deliver our hypothesized cold outbreak. For further reading on what NOAA is projecting with regard to these long range factors, be sure to stop over there and read their latest 2015-16 Winter Outlook. 

So for now, enjoy the relative calm and get ready for Marty, Jennifer and Doc's return on Wednesday, 10/21 as we celebrate 30 years of getting back in time as popularized by the iconic 1985 film. After all, if Marty and friends can accurately predict the Chicago Cubs winning the World Series 3 decades in advance to the exact year, a long range winter projection should be way easier than that, right?

A Look "Back In Time" to 1985...

Contributors to this report included Long Range Forecasters Troy Arcomano, Mintong Nan, Ohio Valley Winter Stormcaster Jason Warren and Editor Rich Foot

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