California El Nino and La Nina Precipitation Climatology
La Niña and  California Precipitation
Jan Null, CCM

October 2018


This is a catalog of California precipitation anomalies for previous la Niña events based upon their strength and the 10 state hydrologic regions.  It has the average for all events, weak events, moderate events, strong and very strong events and the wide range of the individual seasons that went into making up each of the averages.

It cannot be stressed strongly enough that this is a climatological analysis and NOT a forecasting tool.  This is especially true for the averages of different strength events which are made up of what are a very broad range of conditions; some that are decidedly atypical.

The Oceanic Niño Index (ONI) is used to identify El Niño (warm) and La Niña (cool) events in the tropical Pacific. The ONI is the running 3-month mean SST anomaly for the Niño 3.4 region (i.e., 5°N-5°S, 120°-170°W). Events are defined as 5 consecutive months at or above the +0.5° anomaly for warm (El Niño) events and at or below the -0.5 anomaly for cold (La Niña) events. The threshold is further broken down into Weak (with a 0.5° to 0.9° SST anomaly), Moderate (1.0° to 1.4°), Strong (1.5° to 1.9°) and Very Strong (≥ 2.0°) events. For the purpose of this report for an event to be weak, moderate, strong or very strong it much have equaled or exceeded the threshold for at least 3 months.

La Niña Events:
     Weak: 1954-55, 1964-65, 1971-72, 1974-75, 1983-84, 1984-85, 2000-01, 2005-06, 2008-09, 2016-17, 2017-18
     Moderate: 1955-56, 1970-71, 1995-96, 2011-12
     Strong: 1973-74, 1975-76, 1988-89, 1998-99, 1999-00, 2007-08, 2010-11

    

All La Niña Events - Average Percent of Normal Seasonal Precipitation (22 events)
ENSO Type N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
All La NIña 102% 96% 102% 91% 95% 85% 89% 82% 76% 74%
Weak La NIña 97% 94% 102% 90% 97% 85% 89% 89% 77% 85%
Moderate La NIña 115% 105% 110% 102% 97% 86% 91% 67% 73% 53%
Strong La NIña 101% 94% 96% 87% 90% 85% 88% 79% 78% 69%


ALL La Niña Events
All La NIña All La Niña - Years by Percent of Normal Categories (22 events)
% of Normal N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
<80% 6 9 7 10 9 11 9 13 15 15
80-100% 5 4 4 5 3 5 8 6 5 4
100-120% 7 4 6 3 6 4 3 0 1 1
120-140% 2 4 3 3 2 2 0 3 1 1
>140% 2 1 2 1 2 0 2 0 0 1
Average - ALL La Niña
ONI -0.5
1954-55 1955-56 1964-65 1970-71
1971-72 1973-74 1974-75 1975-76
1983-84 1984-85 1988-89 1995-96
1998-99 1999-00 2000-01 2005-06
2007-08 2008-09 2010-11 2011-12
2016-17 2017-18
   


WEAK El Niño Events
Weak La NIña Weak La Niña - Years by Percent of Normal Categories (11 events)
% of Normal N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
<80% 5 6 4 6 5 6 4 4 6 6
80-100% 1 1 2 2 1 2 4 5 4 2
100-120% 3 2 3 1 3 2 2 0 1 1
120-140% 1 1 1 1 1 1 0 2 0 1
>140% 1 1 1 1 1 0 1 0 0 1
Average - WEAK El Niño
ONI -0.5 to -0.9
1954-55 1964-65 1971-72 1974-75
1983-84 1984-85 2000-01 2005-06
2008-09 2016-17 2017-18  
 


MODERATE El Niño Events
Moderate La NIña Moderate La Niña - Years by Percent of Normal Categories (4 events)
% of Normal N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
<80% 0 1 1 1 1 2 1 4 4 4
80-100% 1 0 0 1 1 1 2 0 0 0
100-120% 2 2 1 1 1 1 1 0 0 0
120-140% 1 1 2 1 1 0 0 0 0 0
>140% 0 0 0 0 0 0 0 0 0 0
Average - MODERATE El Niño
ONI -1.0 to 1.5
1955-56 1970-71 1995-96 2011-12


STRONG El Niño Events
Strong La NIña Strong La Niña - Years by Percent of Normal Categories (7 events)
% of Normal N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
<80% 1 2 2 3 3 3 4 5 5 5
80-100% 3 3 2 2 1 2 2 1 1 2
100-120% 2 0 2 1 2 1 0 0 0 0
120-140% 0 2 0 1 0 1 0 1 1 0
>140% 1 0 1 0 1 0 1 0 0 0
Average - STRONG El Niño
ONI -1.5 TO -2.0
1973-74 1975-76 1988-89 1998-99
1999-00 2007-08 2010-11  
 


Percent of Normal (1981-2010) Rainfall for All Years
  Normal 54.75 37.71 19.66 26.37 28.72 20.86 16.88 7.43 18.39 5.49
ENSO Type Rainfall Season N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River
  1950-1951 110% 109% 115% 105% 118% 73% 94% 66% 54% 49%
Mod. El Niño 1951-1952 118% 126% 131% 130% 129% 136% 136% 138% 161% 151%
Weak El Niño 1952-1953 115% 101% 97% 92% 82% 75% 83% 67% 70% 74%
Weak El Niño 1953-1954 106% 90% 79% 74% 81% 76% 83% 75% 90% 72%
Weak La Niña 1954-1955 71% 67% 65% 70% 75% 78% 79% 67% 73% 65%
Mod. La Niña 1955-1956 138% 132% 139% 130% 130% 109% 117% 79% 80% 62%
  1956-1957 89% 82% 89% 73% 80% 71% 78% 67% 77% 52%
Stg. El Niño 1957-1958 146% 140% 126% 151% 131% 159% 142% 121% 156% 127%
Weak El Niño 1958-1959 80% 69% 71% 56% 61% 62% 53% 56% 50% 52%
  1959-1960 87% 80% 70% 74% 74% 70% 68% 64% 68% 95%
  1960-1961 97% 78% 67% 64% 61% 53% 58% 55% 37% 47%
  1961-1962 80% 85% 95% 81% 93% 106% 106% 98% 111% 74%
  1962-1963 115% 119% 132% 120% 109% 102% 96% 69% 53% 42%
Mod. El Niño 1963-1964 80% 67% 81% 61% 69% 62% 72% 75% 76% 90%
Weak La Niña 1964-1965 116% 110% 118% 101% 116% 94% 103% 86% 79% 78%
Stg. El Niño 1965-1966 88% 73% 78% 73% 73% 78% 73% 104% 117% 116%
  1966-1967 107% 120% 131% 134% 133% 133% 142% 102% 130% 72%
  1967-1968 78% 75% 78% 70% 65% 61% 66% 84% 77% 97%
Mod. El Niño 1968-1969 120% 127% 142% 126% 153% 168% 180% 150% 174% 104%
Weak El Niño 1969-1970 110% 110% 111% 99% 96% 74% 77% 57% 59% 73%
Mod. La Niña 1970-1971 118% 103% 116% 92% 87% 78% 82% 72% 77% 55%
Weak La Niña 1971-1972 95% 68% 79% 51% 64% 48% 52% 57% 51% 58%
Stg. El Niño 1972-1973 90% 107% 97% 135% 111% 139% 129% 118% 120% 111%
Stg. La Niña 1973-1974 150% 134% 110% 122% 109% 107% 98% 69% 78% 57%
Weak La Niña 1974-1975 100% 95% 98% 92% 101% 95% 91% 84% 86% 63%
Stg. La Niña 1975-1976 68% 49% 57% 39% 49% 43% 56% 67% 61% 77%
Weak El Niño 1976-1977 41% 43% 69% 46% 47% 66% 63% 102% 84% 112%
Weak El Niño 1977-1978 128% 133% 120% 134% 140% 169% 170% 190% 212% 199%
  1978-1979 73% 80% 80% 83% 97% 97% 101% 116% 129% 143%
Weak El Niño 1979-1980 107% 114% 130% 120% 121% 123% 127% 152% 178% 192%
  1980-1981 74% 74% 77% 65% 69% 75% 73% 73% 60% 65%
  1981-1982 143% 145% 146% 157% 149% 118% 124% 110% 103% 91%
V. Stg. El Niño 1982-1983 155% 163% 159% 187% 180% 196% 186% 190% 195% 187%
Weak La Niña 1983-1984 117% 108% 118% 93% 104% 74% 88% 98% 70% 134%
Weak La Niña 1984-1985 78% 70% 80% 79% 73% 70% 80% 128% 83% 146%
  1985-1986 111% 126% 140% 131% 131% 119% 130% 110% 117% 110%
Mod. El Niño 1986-1987 78% 64% 66% 58% 58% 61% 67% 81% 62% 87%
Stg. El Niño 1987-1988 78% 72% 62% 67% 63% 75% 79% 101% 95% 116%
Stg. La Niña 1988-1989 89% 86% 95% 66% 71% 54% 71% 64% 60% 62%
  1989-1990 74% 76% 76% 64% 73% 54% 63% 50% 56% 45%
  1990-1991 63% 67% 78% 66% 72% 87% 81% 94% 95% 113%
Stg. El Niño 1991-1992 67% 71% 62% 81% 71% 98% 77% 132% 123% 164%
  1992-1993 118% 125% 123% 123% 131% 145% 136% 160% 206% 213%
  1993-1994 62% 63% 64% 65% 60% 70% 71% 53% 73% 65%
Mod. El Niño 1994-1995 139% 161% 162% 150% 156% 176% 161% 145% 174% 137%
Mod. La Niña 1995-1996 119% 115% 124% 119% 109% 97% 98% 67% 71% 32%
  1996-1997 119% 117% 132% 104% 123% 107% 120% 79% 86% 49%
V. Stg. El Niño 1997-1998 145% 158% 128% 173% 152% 203% 179% 180% 198% 169%
Stg. La Niña 1998-1999 111% 96% 109% 90% 89% 80% 79% 74% 54% 60%
Stg. La Niña 1999-2000 93% 97% 86% 98% 100% 100% 90% 70% 69% 54%
Weak La Niña 2000-2001 58% 65% 54% 72% 75% 103% 81% 89% 89% 82%
  2001-2002 93% 86% 76% 89% 82% 63% 76% 41% 32% 25%
Mod. El Niño 2002-2003 111% 104% 90% 103% 89% 96% 94% 92% 105% 76%
  2003-2004 92% 90% 82% 81% 73% 66% 71% 87% 60% 93%
Weak El Niño 2004-2005 98% 108% 108% 122% 130% 151% 132% 187% 209% 212%
Weak La Niña 2005-2006 135% 138% 135% 134% 129% 111% 119% 99% 86% 72%
Weak El Niño 2006-2007 78% 61% 57% 56% 56% 40% 48% 35% 29% 30%
Stg. La Niña 2007-2008 83% 70% 73% 74% 71% 83% 72% 81% 88% 82%
Weak La Niña 2008-2009 75% 79% 81% 76% 83% 64% 71% 74% 66% 83%
Mod. El Niño 2009-2010 102% 95% 90% 107% 103% 111% 108% 99% 109% 117%
Stg. La Niña 2010-2011 115% 124% 141% 118% 145% 130% 147% 129% 136% 96%
Mod. La Niña 2011-2012 87% 71% 62% 67% 62% 61% 65% 52% 64% 61%
  2012-2013 83% 78% 83% 71% 67% 54% 47% 53% 48% 78%
  2013-2014 57% 56% 65% 53% 50% 39% 43% 54% 45% 63%
Weak El Niño 2014-2015 82% 74% 84% 79% 57% 59% 51% 65% 58% 86%
V. Stg. El Niño 2015-2016 112% 104% 121% 95% 103% 82% 98% 96% 72% 74%
Weak La Niña 2016-2017 150% 156% 185% 159% 168% 138% 146% 134% 115% 115%
Weak La Niña 2017-2018 75% 76% 108% 69% 77% 61% 65% 60% 43% 37%
ENSO Type Rainfall Season N Coast Sacramento N Lahontan SF Bay S Joaquin C Coast Tulare Lk S Lahontan S Coast Colo River

 

Copyright © 2018, Golden Gate Weather Services
Reproduction in full or part is prohibited without permission.