What are these lines on a surface map?

[Steven Scott]

In the Southeast, Southwest, and around Montana and Wyoming, you see broken, brown lines.

Are these showing the presence of shortwaves or is it something else?

 

[rdale]

https://www.wpc.ncep.noaa.gov/html/fntcodes2.shtml

 

[Steven Scott]

https://www.wpc.ncep.noaa.gov/html/fntcodes2.shtml

Thanks!