<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>Leonardo,</div><div>Attached are some old scripts I wrote to give a JJA average from a long time series of monthly averages, in this case globally on numerous z levels. There are certainly better ways to prepare the files than this, but here are the steps to use after modifying these:</div><div><br></div><div>First remove the .txt extension. Since these are .exec files, in grads type exec file.exec.</div><div><br></div><div>ga> exec h_sum.exec</div><div>ga> exec h_sum_write.exec</div><div>output is viewed with h_sum.ctl</div><div><br></div></body></html>