(1/5) A Sudden Stratospheric Warming Event (SSWE) - defined as a reversal of the zonal mean winds from westerly to easterly at 10 Hpa (~20 miles above the ground) and 60°N - occurred on February 16th. Another SSWE is expected in late Feb/early Mar.. 
(2/5) The SSWE is "displacing" the Stratospheric Polar Vortex (SPV) off the North Pole and onto the Eurasian side of the globe, and it is forecast to remain there into at least early March. SSWEs often increase, but don't guarantee, the likelihood of colder and snowier weather..
(3/5) An SSWE in Feb. 2018 caused the SPV to "split," with the primary lobe settling over North America & contributing to the onslaught of winter storms in the Northeast during March/April 2018. It often takes 2-3 weeks for SSWEs to begin affecting large-scale weather patterns..
(4/5) However, other factors.. such as tropical forcing and high-latitude blocking patterns.. play a role and can amplify or dampen the effects of an SSWE. So, what does all this mean for snow-lovers in the mid-Atlantic's I-95/I-81 corridors during March? In short, uncertainty..
(5/5) Much is unknown about SSWEs, but they can alter the #JETSTREAM for weeks or even months. For now, I envision a 1-2 week window for snow sometime between Feb. 28 - Mar. 20.. but this is just an "educated guess." Plots courtesy @ECMWF, @TropicalTidbits, & @burgwx. #developing
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