The 7 train started rolling again Tuesday morning with limited local service following a shutdown on Monday.

There is currently no express service as icy conditions continue to pose a problem on the line’s elevated sections, and riders are being urged to switch to the E, F, M and R lines at 74th Street-Broadway if possible.

Rush-hour trains from Flushing were packed to capacity early Tuesday.

Despite the return of 7 train service, Queens straphangers still faced a miserable commute Tuesday after an underground “smoke condition” prevented N and Q trains from reaching Manhattan, the MTA said.

The fire broke out around 9:30 a.m. just north of the 57th Street/7th Avenue stop and took about 40 minutes to extinguish, according to the FDNY.

Manhattan-bound N and Q trains resumed service around noon, but the MTA said it would still be a while before Queens-bound trains started rolling again.

The Office of Emergency Management said an umbrella dropped on the third rail near 52nd Street in Woodside brought the entire train line to a halt Monday morning.

At least five jampacked trains were stuck between stations for almost three hours, causing a logjam in both directions. Limited service between Jackson Heights and Flushing wasn’t restarted until Monday afternoon.

The MTA is still investigating Monday’s transit nightmare.