As if it wasn’t wet enough already this year, new NOAA projection models are showing at least a 60 percent chance that another El Nino will develop before the year is out. California could be feeling the effects as early as July 2017.
Ocean surface temperatures, which were slightly cooler in the current La Nina, are already showing indications of a warming trend. If an El Nino does develop in 2017 that makes two out of the last three years, and that’s a rare occurrence.
For California, an El Nino means there is a high probability of more flooding and coastal erosion and lots of property damage. The current NOAA discussion states that because of the typically high uncertainty in forecasts made at this time of year, an El Nino is far more probable to develop in the September-November period.
El Nino dominates northern hemispheric weather when warmer than average water temperatures occur in the Pacific Ocean near the Equator. During 2015-2016, the weather was off the charts, even for an El Nino. There were some unprecedented occurrences, such as a below-normal hurricane season but record shattering typhoons in the northeast Pacific. And global temperatures set all-time highs, again.
After experiencing a slightly cooler La Nina the last few months, NOAA has just declared the equatorial Pacific as neutral again. For the foreseeable future, the prevailing weather pattern is neither La Nina or El Nino.
The next NOAA forecast update is scheduled for March 9. At that time, the weather for the rest of 2017 and the latest El Nino models will be based on more predictable models.
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California is currently experiencing one of its wettest winters on record. Precipitation has been especially remarkable across the Northern Sierra watersheds, where liquid equivalent (rain+melted snow) is presently above 200% of average.
In addition to the “typical” flooding of regional rivers and streams that is expected with prolonged heavy precipitation, California’s vast water storage and conveyance infrastructure is starting to crack under the strain — in some cases, quite literally (Oroville Dam).