Photograph of a makeshift stop sign, since traffic lights were out, at Bergen St. and Flatbush Ave. by steuben on Flickr

Yesterday afternoon, a few manhole fires caused a load of problems for Brooklyn residents in the middle of a sweltering weekend.

One fire, at Smith and Dean Streets in Boerum Hill, seriously compromised subway service for the G, F, and 4 lines, not to mention affected the 2 and 3 lines. WNBC explained that the fires caused as "resulting loss of alternating current power for the signal system," which meant delays and disruptions. The fire only affect the signal system, not rail power, so no one was trapped and all trains had air-conditioning--the trains just moved slowly. Power was also out in the neighborhood, starting around 5:45 p.m. and didn't come back on until the middle of the night.

There were two other manhole fires: One in Flatbush that reportedly affected 300 customers and another in Williamsburg that hit 150 customers. Con Ed said it wasn't sure if the fires were in part due to the hot weather and thunderstorms.