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Why La Nina (or any other Nino or Nina) Will NEVER Give A "Precise" Winter Forecast

"Never" is a strong word.

I have never used the word never when talking about the weather in my 15 years doing this for a living.

Until today.

Today, I'm making this statement:  La Nina, or any other type of atmospheric phenomenon, will never be able to make a precise forecast for winter weather in Western Washington.

There's a key word in that statement.  Try to find it.  I'll give you the answer later.

I know what you're thinking.  "Funny that Paul makes this statement now instead of October."  That thought is actually spot-on.  I needed to live -- and work -- through a La Nina-fueled, Twitter-and-Facebook-and-iPhone-weather-forecast-app-enhanced winter here in the great Pacific Northwest.

I'll admit it.  I bought into the La Nina hype back in early autumn.  It was shaping up to be the strongest La Nina episode in 55 years, and even though this meteorologist never guaranteed a crazy winter... all signs were pointing in that direction.  Take a look at a video I posted on La Nina back in October:

I know exactly what I said, as I still have the notes I used.  Wetter than normal fall and early winter.  Colder than normal mid-to-late winter.  Increased snowpack.  Good chance of more lowland snowfall.

Here's what we all heard, including myself:  MORE SNOW AT MY HOUSE.

Admit it.  That's all that 99% of us care about.  Snow or no snow.  It's really that simple.  We know it's going to be chilly in winter.  We surely know it's going to rain.  We've got a pretty good handle on the fact that it snows in the mountains.  But we Western Washingtonians have a unique fascination with lowland snowfall. 

Merely utter the word "snow" in a Seattle coffee-shop, and six of your latte-loving neighbors will utter comments like "I love snow" or "I can't stand snow" or "I need to fly to Cabo".  Snow ignites a palpable passion within us.

Every chance of snowflakes this winter, from Darrington to downtown Tacoma... from Bellingham to Bothell to Ballard... literally lit up social media.  Most of these snow chances ended up with more "fizzle" than "sizzle".  A lot of you snow-lovers were disappointed time and time again.

I have literally received more than 100 e-mails asking why La Nina hasn't done what she promised.

Here's something that may shock you:  La Nina did do most of what we expected.  KOMO meteorologist Scott Sistek wrote a great blog on this subject (click here to read it), giving La Nina a B- for the winter.

Wetter than normal fall/early winter.  Check.

Colder than normal mid/late winter.  Check.

Big snowpack?  Thanks to a late rally, check on that, too.

Increased lowland snowfall?  Well, not so much.

Before I go further, let's do a little "La Nina 101".  La Nina doesn't make it snow.  La Nina is cooler-than-normal water in the equatorial Pacific Ocean, and this chilly change impacts how storms and cold air move through the atmosphere, especially in winter.  It has -- and never will be -- a guarantee.  It's kind of like being given a beach ball to throw at a target instead of a ping-pong ball.  You have a much better chance of hitting the target, but you still have to throw the ball properly.

Lowland snow provides a unique quandry.  We need the cold air and the moisture to move over us simultaneously, and that marriage-in-the-sky isn't so easy to do in this part of the world.  Face it, it's hard to get a good snowstorm in Seattle.

Which brings me back to my original statement, "La Nina will never be able to make a precise forecast for winter weather in Western Washington".  The key word in that phrase is "precise".  It's the year 2011, and if we can cram 16 gigabytes of information in a phone in your pocket, I understand your desire for a guaranteed forecast for a snowy winter at your house.

Not going to happen.  Not even with La Nina.

Saying "colder than normal late winter" and being correct reflects good accuracy.

Saying that "The city of Seattle is guaranteed to have at least one big snowstorm this winter and is a lock to get more than it's average of 11" snow" would be an attempt at precision.

That type of precision -- several months out -- will not happen in my lifetime.

Here's the reality:  Folks in Seattle, Bellevue, and other snow-starved sections of King & Snohomish Counties will call this La Nina a "bust".  Strictly looking at snowfall at their house, they're right.  But that's just one paramater of a La Nina episode in one tiny part of Western Washington.  A tiny part that's home to 2,000,000 people!

The genesis of this blog is actually the Hurricane Season of 1992.  If you just look at the numbers, it was one of the "wimpiest" hurricane seasons on record.  Only six tropical cyclones were strong enough to be given a name that year.  Normal is twice that amount, and we've had two hurricane seasons recently with more than 20 named storms.

The first named storm of the 1992 hurricane season didn't form until nearly half of the hurricane season was finished.  By any indication, this was a very, very slow year for hurricanes.

Don't tell residents of Miami-Dade County that.  Take a look at what happened next:

Total devastation.  A direct hit on Homestead, Florida.  I worked at that station, WTVJ, for four years before moving back to Seattle.  Discussing that storm with residents there brought tears to their eyes, even two decades after Hurricane Andrew hit.

Here's my point:  All it took was ONE bad storm to make it a bad hurricane season in 1992 in South Florida.  People won't remember only 6 named storms.  They remember Andrew.

There is a parallel to be used here.  We have, do, and always will judge "good or bad" winters by the presence -- or lack -- of a big snowstorm.

Big snow in 2008-09.  Bad winter.

No snow in 2009-10.  Wimpy winter.

This year?  Depends on where you live, but more than likely you're leaning "wimpy".

All it takes is one storm -- one snow-storm -- to have that winter be imprinted in your brain's synapses as a "bad winter".

And as good as forecasting the weather is getting, predicting one big storm several months out is going to stay science fiction for a long time to come.

 

-- Paul