It’s coming. Not senior skip day—snow days.

Usually, when people think of massive snow storms, they recall Snowmageddon in 2010. Little do they know that this was only classified as a “moderate” El Niño storm—despite the several feet of snow we got. Snowmageddon was caused by El Niño, otherwise known as ENSO.

El Niño occurs when an unusually warm current of ocean water appears in the Pacific Ocean—followed by high air pressure in the western Pacific and low air pressure in the eastern Pacific. Results of El Niño vary from wetter weather in southern California, drier weather in the Pacific Northwest, and larger winter storms on the east coast.

Typically, El Niño occurs once every seven years with moderate El Niño occurrences happening sporadically in between these seven years. The last El Niño before Snowmageddon was in 2007—seven years ago.

Although this 2007 storm was classified as “weak,” it resulted in at least 38 deaths in North America, mostly car accidents. Therefore, whatever El Niño we experience this year could have varying results—from school delays to plane cancellations, and increases in traffic.

Even though this winter storm would mean more snow days for us (and less school), it could be very problematic for California. This El Niño could potentially make California even drier—not helping the severe drought they are experiencing right now.

The federal Climate Prediction Center in College Park predicts that there is a two in three chance that El Niño will occur this year. However, earlier in the year forecasts predicted there was a 90% chance El Niño would happen near December. Since then, there have been little atmospheric and ocean changes—typically characteristic weather patterns before El Niño. Due to limited changes, the likelihood percentages of El Niño happening have dropped significantly.

However, even though the intensity of El Niño is debated by various weather networks, for the most part they are all in agreement that it will still occur around December.

So, once again, it’s coming. I would highly suggest investing in an Eskimo suit.