Faire d'income: Yep. Yesterday DTW Michigan only had light rainshowers forecast, but within about 30 minutes level 6 thunderstorms developed (after landing waited one hour on ramp-it was shutdown). We must know what nearby airports are suitable alternates (mostly when no alternate airport or fuel is planned, as is quite common, even if light rain is in forecast) for any place. If we had come in about ten minutes later, we would have asked ATC whether the full length runway was available at Toledo, Ohio, maybe Windsor, Ontario. We had just told DTW Approach that we needed to go to Toledo, and suddenly
they said that we could get into 03R with limited vectoring.
Never use up most of your cont. fuel far from your destination.