(CN) - Scientists say the current El Nino has matched the 1997-1998 pattern for the strongest on record and that any effect on California's record drought has likely just begun.
In its monthly El Nino update released Thursday, the National Oceanic and Atmospheric Administration said the three-month average of sea-surface temperatures was 2.25 degrees Celsius above average, equaling the same period in 1997. The current weather pattern broke the December ocean-surface temperature record dating back to 1950, at 2.38 degrees Celsius above average.
According to NOAA's prediction models, surface temperatures are likely to decrease over the next several months, leaving a slim chance that January's update will elevate El Nino to the strongest since records have been kept.
Scientists declare an El Nino event when water temperatures in the equatorial Pacific Ocean rise above normal for three consecutive months. The weather pattern can cause droughts in Australia and India while saturating much of the western United States with above-average precipitation.
While El Nino may weaken in terms of surface temperatures, its impact in terms of precipitation for California is just ramping up. Historically the Golden State feels the brunt of El Nino's punch beginning in January and forecast models are predicting above-average precipitation across the state.
In 1998, the strongest El Nino year recorded, most of the tumultuous weather occurred in February. That month, downtown Los Angeles received 13 inches of rain - almost equal to its yearly average. El Nino-driven storms that winter killed 17 people and caused an estimated $500 million in flood damage.
Thursday's El Nino update comes as most of Northern California is preparing for a punch of winter storms. Forecasters are predicting several feet of snow in the Sierras over the next week thanks to a pattern of storms lined up in the Gulf of Alaska.
Despite above-average rainfall and snow in December and January thus far, California remains mired in drought and its reservoirs are in worse shape than they were last January. The winter storms have brought healthy snow to ski resorts but forecasters warn there is no certainty that California's snowpack will continue to build during El Nino.
"The January-through-March forecast still had a tilt in the odds toward warmer than average temperatures but individual storms can differ within the season," NOAA meteorologist Tom Di Liberto said in an email.
Along with warming temperatures in the tropical Pacific, NOAA's monthly update found the atmospheric ingredient to El Nino also picked up. This past month, satellites picked up more clouds than average, surpassing December figures from the monster El Nino years 1982 and 1997.
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