Doing some research. See the things you thought you’d never need beyond college? Tomorrow’s science report is about our lack of winter. Since late October we’ve had hardly any snow.
We are not alone! Much of the Mountain West has been snow free for the winter season. Meanwhile portions of Siberia and Alaska have gotten (and are getting) pounded!
I tend to concentrate on the Northeast. This is not the kind of thing I usually look at. I know where to find people who do.
This afternoon meteorologists Rachel Frank, Bob Cox (WTIC radio) and I had a phone conversation with a meteorologist from NOAA’s Hydrometeorological Prediction Center. HPC makes maps like these and predicts significant weather events on a national “big picture” basis.
Before I tell you what he told us you should understand the atmosphere is infinitely complex. Everything that happens affects everything else! You know, if a butterfly flaps his wings in Brazil it changes things in an unpredictable way that makes long range forecasting impossible.
The atmosphere is a cacophony of this then this then this then this then…. It’s never static.
Observations in the Pacific show we are in a La Nina period.
La Nina is the opposite of El Nino. We’re seeing colder than normal water extending from the South American coast into the mid-Pacific. Typically La Nina means less snow in the Northeast.
La Nina isn’t very unusual. There’s more.
The North American Oscillation Index has been mainly positive. The index constantly fluctuates in intensity and is subject to flipping every few weeks. This year it’s locked into it’s pattern.
Strong positive phases of the NAO tend to be associated with above-averagel temperatures in the eastern United States and across northern Europe and below-average temperatures in Greenland and oftentimes across southern Europe and the Middle East. They are also associated with above-average precipitation over northern Europe and Scandinavia in winter, and below-average precipitation over southern and central Europe. Opposite patterns of temperature and precipitation anomalies are typically observed during strong negative phases of the NAO. During particularly prolonged periods dominated by one particular phase of the NAO, anomalous height and temperature patterns are also often seen extending well into central Russia and north-central Siberia.
And that’s what’s happened! It’s been a brutal winter in Siberia and Alaska–much more harsh than normal.
Like La Nina a positive NAO isn’t earth shattering news, but the two coming together simultaneously has a cumulative effect.
I’m not wishing last winter on us, but patterns change and we’ll surely have some winter before the flowers bloom.