Don't forget to look for 'mtw' on the met office wind charts. Mountain Wave - the stuff you had a brush with a few months back. If it's forecast use that low level around the mountains route.
RASPtableGM
This is the website glider pilots use to work out if it's a wave day. You need to check in the morning of the day you plan to fly. Click the 'press for full parameter set' button and then select 'vertical velocity at 850mb'. Green & yellow strips, maybe with some red, = wave probably around. Easterly wave is showing right now.
RASP will also show if it's going to be thermic.