UPDATE: Trains resumed with minor delays on the Brown Line as of midday Monday. Service on the CTA Brown Line was shut down during rush hour Monday morning due to track conditions on Chicago's North Side. What we know:CTA officials said around 7:45 a.m. that no trains were running between the Kimball and Southport stations due to poor track conditions. Trains are still in service between the Belmont and Clark/Lake stations. The CTA is advising riders to allow extra time for travel and consider taking alternative routes such as buses.