Night! Different matter. Call every Tom, Dick and Harry with a radar to find a route. If there's a long line across track or the sky is littered with them, wait another hour and ask again. If the TS are still not dissipating, call it a night and hit the pub for a beer and a countermeal and get a fresh start in the morning. No point in fretting over the decision. Better to be on the ground wishing, etc.