Rain: During the next heavy rainstorm WITHOUT lightning, grab an umbrella and go outside.
Walk around your house and look around at the roof and property. A rainstorm is the perfect time to see how the roof, downspouts and grading are performing. Observe the drainage patterns of your entire property, as well as the property of your neighbor. The ground around your home should slope away from all sides. Downspouts, surface gutters and drains should be directing water away from the foundation.
One important maintenance task - is to monitor and maintain the drains and piping. Drains and piping should be open and clear of leaves, earth and debris. A garden hose can be used to check water flow, although its discharge cannot approximate storm conditions.