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Pacific Storm Impacting the West; Critical Fire Weather Returning to Central U.S.

A Pacific storm will move through the western U.S. Monday and Tuesday with areas of heavy mountain snow, gusty to high winds, and lower elevation rain. Ahead of this storm, gusty winds and dry conditions over much of the central and southern Plains will contribute to widespread critical fire weather conditions Monday and Tuesday. Read More >

Monthly Precipitation Anomalies


Figure 3


a)


Monthly Precipitation Anomalies El Nino

b)


Monthly Precipitation Anomalies La Nina


Fig. 3. Total precipitation deviation from the monthly historical average during (a) El Niño and (b) La Niña events. Composites are made from all the historical El Niño or La Niña events.



Figure 4


a)


Monthly Precipitation Anomalies El Nino

b)


Monthly Precipitation Anomalies La Nina


Fig. 4. Total precipitation deviation from the monthly historical average during (a) El Niño and (b) La Niña events. Composites are made from all the historical El Niño or La Niña events.

Both Fig. 3 and Fig.4 show the deviation from the monthly total precipitation relative to historical average given in Fig. 2. and Table 1. However, the information in Fig. 3 is in unit of inches, while that in Fig. 4 is presented by percentage.
 
The monthly total precipitations at all six stations are slightly more than historical average during the El Niño year. However, from January to June of the year after an El Niño event, there is deficient precipitation. The maximum difference could reach as much as 3 inches (around 80%) less than its historical average amount at one station. During a La Niña event, on the other hand, moderate deficient precipitation took place in the first half of the La Niña year. While from October to the end of the next year there is more precipitation. Usually, there is 1-2 inches, or 20-40%, more than the historical average.
 

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