ENSO and rainfall

With so much emphasis on forecast models its prudent to look at statistics under this scenario;

• When the oceans are in this state (RHS image) there is a high probability that above median rainfall will occur in the next 4 month period at Burren Junction;

• A La Nina condition has profound affects on the Rowena growing Season Rainfall at Rowena. The botton chart shows La Nina (dark blue), neutral (light blue) and El Nino (red) state, based on a fairly couse assumption on the Nino3.4 index at years end;

• With LT average for that location being around 288mm, the worst case scenario over the analysis period looks to be average, with many La Nina totals well exceeding average;

• Post-January, the correlation with ENSO decays and other factors such as the MJO take over.