Storm spotters regularly seek out inflow bands to warn people of incoming inclement weather, as they are directly correlated with wild storms. Inflow bands never show up unless there is a nasty storm brewing, so you should look for high, covered ground 100% of the time.
Bright Green or Stinky Water
Water that has been sitting for a long time will generally develop a mildewy/sulfuric odor that indicates an influx of harmful bacterial cultures that will make anything that drinks out of it sick. Additionally, if you see stagnant water with the development of bright green algae in it, stay as far away as you can.