El Nino / La Nina Rainfall Comparison

ENSO - El Niño / La Nina Information for Site 234

ENSO (El Niño Southern Oscillation) is the warming and cooling of the ocean water along the Equator in the Eastern Pacific Ocean near South America. The warm phase is called El Niño and the cold phase is called La Nina.

When the Eastern Pacific Ocean is 0.5 degrees Celsius above normal for 5 consecutive 3-month average periods, an El Niño is declared. When the Eastern Pacific Ocean is 0.5 degrees Celsius below normal for 5 consecutive 3-month average periods, a La Nina is declared.

The El Niño and La Nina are declared as Weak, Moderate, or Strong depending on how far from normal the water temperature gets. When the temperature is above 1.5 degrees Celsius, it is declared as strong. When the temperature is above 1.0 degrees Celsius, it is declared as Moderate. When the temperature is above 0.5 degrees Celsius, it is declared as Weak.

The effect on Ventura County trends to be wetter with El Niños and drier with La Ninas. Although the top driest years have been Neutral or Weak or Moderate El Niños.

Data for calculating ENSO Index (ONI) is provided by the Climate Prediction Center.


Strongest El Niños

#Water
Year
IntensitySiteSeason
Total
Percent
Normal
12016+2.5234B - Las Llajas Canyon8.4758.0%
21998+2.3234A - Las Llajas Canyon37.22254.9%
31983+2.1234A - Las Llajas Canyon32.97225.8%
41973+2.0234A - Las Llajas Canyon16.06110.0%
51958+1.7234A - Las Llajas CanyonN/AN/A
61992+1.6234A - Las Llajas Canyon27.10185.6%
71966+1.5234A - Las Llajas CanyonN/AN/A

Top 10 Wettest Years

#Water
Year
SiteENSO StateIntensitySeason
Total
Percent
Normal
12005234B - Las Llajas CanyonWeak El Niño+0.738.54264.0%
21998234A - Las Llajas CanyonStrong El Niño+2.337.22254.9%
31983234A - Las Llajas CanyonStrong El Niño+2.132.97225.8%
41978234A - Las Llajas CanyonWeak El Niño+0.832.27221.0%
51993234A - Las Llajas CanyonNeutral+0.327.55188.7%
61992234A - Las Llajas CanyonStrong El Niño+1.627.10185.6%
71995234A - Las Llajas CanyonModerate El Niño+1.026.29180.1%
81980234A - Las Llajas CanyonWeak El Niño+0.623.28159.5%
92011234B - Las Llajas CanyonModerate La Nina-1.422.41153.5%
101969234 - Las Llajas CanyonModerate El Niño+1.020.82142.6%

Strongest La Ninas

#Water
Year
IntensitySiteSeason
Total
Percent
Normal
11974-1.9234A - Las Llajas Canyon14.72100.8%
21989-1.8234A - Las Llajas Canyon10.4671.6%
31976-1.6234A - Las Llajas Canyon10.0168.6%
42000-1.6234A - Las Llajas Canyon12.4985.5%

Top 10 Driest Years

#Water
Year
SiteENSO StateIntensitySeason
Total
Percent
Normal
12014234B - Las Llajas CanyonNeutral-0.54.8233.0%
22002234A - Las Llajas CanyonNeutral-0.25.5137.7%
31990234A - Las Llajas CanyonNeutral+0.15.5137.7%
42007234B - Las Llajas CanyonModerate El Niño+1.05.6939.0%
51987234A - Las Llajas CanyonModerate El Niño+1.25.8139.8%
62013234B - Las Llajas CanyonNeutral-0.46.1642.2%
72004234B - Las Llajas CanyonNeutral+0.37.7152.8%
81972234A - Las Llajas CanyonWeak La Nina-0.88.0054.8%
92016234B - Las Llajas CanyonStrong El Niño+2.58.4758.0%
102018234B - Las Llajas CanyonWeak La Nina-1.08.7059.6%