\label{fig:sam_composite}
Composite mean 500 hPa streamfunction zonal anomaly for days (with 30-day running mean applied, 1979-2014) where the PWI was greater than its 90th percentile and the AOI is greater than its 75th percentile (gray) or less than its 25th percentile (black). Dashed contours indicate negative values and the contour interval is $4.0 \times 10^6 \: m^2 s^{-1}$. 
    
    