NPR Stations In Lancaster

Does anyone listen to NPR while driving between Lititz and Lancaster? I have noticed on some days (maybe it's related to weather in some way?) that 89.5 and 99.9 get second channels buzzing in and it's impossible to follow anything. Usually 89.5 works well for me north of Lancaster City and in Lititz and 99.9 works better in Lancaster City.

Anyone else deal with this? Any suggestions for other stations?