I tore the elbow of my windshirt this weekend. It is a 1 inch linear tear, only slightly frayed, but in a high tension area. I was thinking about zigzag sewing it and then applying some seamgrip or silnet, but have not done this before. Any suggestions on the most durable fix and one that will withstand some washing? Do I need to patch it in that area?
Sewing (other than suturing wounds)is not one of my strong suites, so I'd appreciate any suggestions.

A patch would be the strongest repair. I have had good luck with ripstop repair tape also. You could go the pants and suspender route and use the repair tape and then sew the perimeter of the tape too.

+1 on the patch.

I used McNett Seam Grip to repair a rodent chewed pack - high tension

Put on top of some plastic, glue it, let it dry, peel off plastic. Try this first on a scrap to make sure it works as planned. Dried seamgrip will stick to itself so you have to wipe some talc on it afterwards.

Or a patch would work too.

Or do like the thread where the person is ripping a hole, putting in down, and sewing it back up. Pull in the fabric, do a bunch of stitches. This will require that the fabric is bigger around so there'll still be enough room when you're done.

Spinnaker tape, or Tenacious tape is pretty effective for this sort of repair. It's what spinnaker tape is intended for, after all...