To plot traces of the mean & max pdfs, compute the mean and std of the measurement of interest (I can't tell from this figure if its supposed to be pressure or temperature) then plot the pdf.
mew = mean(x); sig = std(x);
y = 1/sqrt(2*pi*sig^2)*exp(-(x-mew).^2/2/sig^2);
plot([y y(1)],[x x(1)],'k--')