hallo. whwn I plot a wind field alone, it's ok, when I overplot the same wind field over a contour there is one strange line starting from one or more of the corners and going out of the plot area without significance. how can I resolve this? -- Dott.ssa Giulia Clai ENEA CA.MO. via Martiri di Monte Sole, 4 I-40129 Bologna, Italy