Elongate portable sign

<figref idref="DRAWINGS">FIG. 1</figref> is a perspective view of a new, original and ornamental design for a elongate portable sign in accordance with the present disclosure;

<figref idref="DRAWINGS">FIG. 2</figref> is a front elevation view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>;

<figref idref="DRAWINGS">FIG. 3</figref> is a right side elevation view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>;

<figref idref="DRAWINGS">FIG. 4</figref> is a left side elevation view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>;

<figref idref="DRAWINGS">FIG. 5</figref> is a rear elevation view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>;

<figref idref="DRAWINGS">FIG. 6</figref> is a top plan view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>; and,

<figref idref="DRAWINGS">FIG. 7</figref> is a bottom plan view of a elongate portable sign shown in <figref idref="DRAWINGS">FIG. 1</figref>.

All features shown by broken lines represent unclaimed portions of the design.