The 2012-2013 drought affected the entire North Island plus the west coast of the South Island.
It was one of the most severe droughts to have impacted these areas in at least 40 years, and in some cases more like 70 years. The economic impact of the drought is estimated to be, at a minimum, $1.3 billion (Ministry for Primary Industries, June 2013).
Download the NIWA report (and/or the 2-page summary), prepared for the Ministry for Primary Industries in June 2013, on the extent and severity of the 2012-2013 drought. Figure 3-2 from this report (also shown on this page), shows the relative rank of the 2012-2013 drought compared with all other years since 1972-1973, using Potential Evapotranspiration Deficit (PED) as a drought indicator.
Below is a sequence of soil moisture deficit (SMD) maps and monthly and 3-monthly rainfall decile maps which show the progression and recession of the drought from October 2012 to May 2013: