Another Meteorological Term to Chew On

You often hear terms such as La Nina , El Nino, North Atlantic Oscillation (NAO), Arctic Oscillation (AO) and the PNA (Pacific North America) pattern. All of these influence the weather around the world and are connected to each other in some way.

This next one is supposedly playing a major role in our wildly unpredictable winter weather thus far. So far this year, long-term weather model predictions have been virtually useless, more than three or four days out.

So, here is another to ponder:

Madden-Julian Oscillation (MJO) - Tropical rainfall exhibits strong variability on time scales shorter than the seasonal El Niño-Southern Oscillation (ENSO). These fluctuations in tropical rainfall often go through an entire cycle in 30-60 days, and are referred to as the Madden-Julian Oscillation or intraseasonal oscillations. The intraseasonal oscillations are a naturally occurring component of our coupled ocean-atmosphere system. They significantly affect the atmospheric circulation throughout the global Tropics and subtropics, and also strongly affect the wintertime jet stream and atmospheric circulation features over the North Pacific and western North America. As a result, they have an important impact on storminess and temperatures over the United States. During the summer these oscillations have a modulating effect on hurricane activity in both the Pacific and Atlantic basins.