my old instructor told me.

if you die in a plane crash on a day with low overcast, low vis, with thunderstorms all around knowing you shouldn't have gone,, the day they bury you will be clear and a million with lots of sunshine.

we had this same scenario happen to us just yesturday. it was our last leg home. we sat in dsm for 2 1/2 hours waiting for storms to get out of mem. they told us we could launch but everyone was holding. my captain was smart enough to say we will wait it out and sure enough after about 30 min on the ground dsm tower told us that they were putting a stop on all flights into mem and that everyone that was holding had to divert. is diverting a big deal? no, had to do it several times. but taking the risk of launching a plane when you know everyone is holding to try and get in wouldn't have been smart. we just waited it all out, took off and had a smooth non eventful flight into mem.