When approaching weather it is often the case that clouds will start out as high clouds that have a scattered or few coverage. Then as you get closer to the main weather feature, the clouds will become broken to overcast and will "build down" toward the surface. Below is the prog chart valid at 00Z for a flight from Charlotte, North Carolina to Kansas City, Missouri and it's clear that the flight is originating from high pressure (fair weather) and flying toward an area of low pressure (deteriorating weather).
The EZWxBrief clouds display on the EZRoute Profile shown below provides a simple visualization of this for that same route departing at 20Z. EZWxBrief uses the winds aloft forecast to calculate the groundspeed and pulls the forecast from the appropriate times from the expected arrival points along the route. This clearly shows the scattered or few clouds that are lingering at 15,000 feet and higher that eventually "build down" to 4,000 feet toward the surface as you get closer to the areas of precipitation expected in Kansas City.
Most pilots are weatherwise, but some are otherwise™
Dr. Scott Dennstaedt
Weather Systems Engineer
CFI & former NWS meteorologist