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Expert Advice: How Big Will El Niño Be and When Will It Hit?

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As we close in on the holidays, thousands are waiting for something beyond presents under a tree. Many people are anticipating a storm that they are hoping will be a drought game changer for California. Each new round of rain (the latest passing through today) has readers asking is El Niño here? We've written about what the infamous winter storm is and its predicted impact. The only question that remains: When is it going to arrive? We went to NBC Bay Area's Chief Meteorologist Jeff Ranieri for some straight talk.

Everyone is talking about when the El Niño rain will hit. What is your opinion?
Ranieri: "According to the latest forecast modeling data, we'll have the best chance of above average rain with El Niño enhanced storms January to March. I really think we'll have a great shot at getting at least average rain and then some for the greater Bay Area."

Will it be as big as the 1997 El Niño?
Ranieri: "Not likely, it's not showing as strong of characteristics. The bottom line, nobody knows exactly how many storms and exactly how much rain."

How strong will this El Niño be?
Ranieri: "It currently ranks an impressive #2 historically when looking at the Oceanic Niño Index or (ONI). The ONI measures the warm equatorial Pacific temperature over a three-month period. The latest observation for September, October, and November is at 2.0°c , The strong event of 1997 had the same period ranking a warmer 2.2°c."

What part of the state will get the most rain?
Ranieri: "The highest risk of rain due to El Niño related storms exists across Southern California January through March with 65 percent chance of above average rain. This is due to El Niño impacts generally moving in from the Equatorial Pacific. The Bay Area will have a 55 percent chance of above average rain."

While rain is important, snowpack is the biggest factor when it comes to drought. Will we get more Sierra snow with El Niño?
Ranieri: "There's a big misconception that El Niño means no Sierra snow. That's just not true. In fact, since October we've already accumulated 4 to 7 feet of snow across the Sierra with our current El Niño phase. In the past there have also been years with heavier snow during El Niño. During the 1997–98 event there was 115 percent of average statewide Sierra snowpack; in the 1982-83 event, the statewide Sierra snowpack averaged 180 percent. Some of the El Niño related storms may be warmer, but again it doesn't mean no Sierra snow."

Do you think it will be as bad as FEMA (Federal Emergency Management Agency) and local officials predict?
Ranieri: "FEMA is doing what they should and getting the word out so people are prepared. All it takes is one storm producing copious amounts of rain in a 24-hour period and that can set off flash floods. The best way to be ready, especially if you live near a creek, river, or stream is to have sandbags and know the evacuation route. Everyone should have a storm kit for not only the rain but our daily chance of earthquakes. This means the basics—like enough bottled water for a few days, batteries, flashlights, and food that you can store. If things turn bad it's always better to be prepared."

What are some of the areas that could be prone to problems, such as flooding?
Ranieri: "The biggest areas prone to flood risk will be anywhere fires occurred this past year, such as the areas near the Valley and Rocky fire sites, where 140,000 acres were burned. The burn scar areas have no vegetation to hold in the ground, so land and mudslides will be the greatest risk in those zones. Anyone living on a hillside should also be alert if and when strong storms arrive. Planting vegetation and ground cover is one of the best ways to help secure your hillside."

Will this El Niño be the answer to our drought?
Ranieri: "Not likely. Sierra snowpack was at historic lows during 2014 and early 2015. Plus, there's a four-year rain deficit roughly 30.00 to 50.00" for many cities. We do need to begin somewhere and this El Niño could give us the jump we need find our way out of this drought."

· Previous El Niño Coverage on Curbed [Curbed SF]