Seasonal Diagnostic and Predictability of Rainfall in Subtropical ...

15 FEBRUARY 2000 MONTECINOS ET AL.
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FIG. 4. Wetness and dryness classes obtained by stratification analysis considering warm cases, for each of the 12 sliding bimonthly
periods: DJ, JF, FM, up to ND. Class symbols are included on the bottom of the figure.
this bimonthly interval, but it disappears during AS. In
Chile, the tendency for anomalously wet conditions
seems stronger in AS, when the rainfall is decreasing
in the annual cycle (Fig. 1).
The results of stratification analysis for anomalously
cold conditions in the central equatorial Pacific (Fig. 5)
reveal a relatively weak rainfall–SST relationship. Specifically,
during the first semester of the year (DJ–MJ
bimonthly intervals), only in northern central Chile is
a weak tendency for anomalously dry conditions during
the onset of the rainy season (AM) observed. In Chile,
the most significant features during the second semester
of the year is the tendency for below-normal rainfall (or
at least not wet conditions) in northern central sector
(30–35S) at the height of the rainy season (JJ), and
more to the south (33–37S) during the spring (SO).