By Reginald Stanley. Posted July 2, 2018, 7:19 PM.

Another weak La Nina pattern in the equatorial Pacific Ocean took place during the 2017-2018 winter, for the second year in a row. However, unlike the previous water year, the region consistently received below-average rainfall during the 2017-18 water year.

The rainy season was marked by a particularly long dry streak that lasted from August 2017 all the way into early January 2018, during which very little or no rainfall occurred across most of the region. Stubborn high pressure dominated most of the entire winter, with a severe Santa Ana Wind event in December sparking multiple wildfires. The only notable storm activity occurring in a three-day period in early January and most of the month of March. The January storm was by far the wettest period of the 2017-18 rainy season, with many Inland communities receiving between 2 and 4 inches of rainfall. Storm activity resumed in March, however these storms were much weaker and barely padded already very low season totals.

Of the eighteen currently active WeatherCurrents stations, all of them recorded season totals less than 10 inches. This also occurred in the 2013-14 water year, of which many stations in 2017-18 recorded similarly low season totals. In Downtown Los Angeles, where records date back to 1877, the 2017-18 water year was the third-driest in recorded history - with only 2001-02 and 2006-07 being drier. In San Diego, where records are available dating back to 1850, the 2017-18 water year was the second-driest in recorded history there, where only 2001-02 was drier. In Temecula, where such records date back only to 2000, it was the fourth-driest. The dismal water year has allowed drought conditions to return or worsen in much of the state of California, which had seen slight relief following the above-average 2016-17 water year.

The Climate Prediction Center issued an El Nino Watch on June 14, for the 2018-19 winter. This indicates that the chance for ENSO conditions (being neutral through the summer) increases to 50 percent in Fall 2018, and 65 percent during Winter 2018-19. In the past, El Nino episodes were typically associated with above-average rainfall in Southern California. However this is not always the case, as a number of El Nino episodes failed to result in wet winters for the region many times, with a particularly noteworthy case occurring during the strong El Nino episode of 2015-16 - which instead yielded a disappointingly below-average rainy season across the region. More information will be posted in the following months.

The water year in Southern California runs from July 1st through June 30th.

Here are the season totals for the WeatherCurrents network and associates:

Note: Season Averages were only given for stations with at least five complete years of data. Even these averages may be skewed from many dry years or unusually wet ones, and should not be interpreted as the actual average rainfall for those communities.