This outlook is based upon the Jan to Feb 2016 NINO3.4 SST Anomalies extended (NINO3.4 SST Anomalies)
Rarotonga 3mth (Apr to Jun 2016) Rainfall outlook. Based upon the 2mth Average value of the NINO3.4 SST Anomalies during Jan to Feb 2016 ( NINO3.4=2.22 ), the forecast is biased towards "below-normal" Rainfall conditions for April through to the end of June for Rarotonga, with a forecast probability of 52%. The chance of "above-normal" Rainfall occurring is 12% while the chance of "normal" Rainfall is 36%.
Another way of looking at this, is that given the current climate conditions, in about 5 out of every 10 years, the Rainfall in the April-June period are expected to be "below-normal"; about 4 out of 10 years are expected to be "normal"; and about 1 out of 10 years are expected to be "above-normal".
"Below-normal" Rainfall for the April to June period at Rarotonga includes Rainfall less than 373mm.
"Above-normal" Rainfall is that which is greater than 487.7mm.
"Normal" Rainfall lies between 373 and 487.7mm.