LYNN – Officials are reminding residents to be aware of the city’s elderly and to use caution as chilling temperatures head into the region.”We have yet to come to time where we have had to turn people away from beds, and have yet to hit capacity either, so we’ve got a little bit of a buffer zone,” Lynn Shelter Association Street Advocate Patrick Byrne said. “But this is going to be the toughest part of the month, because it’s getting colder and we’re getting farther and farther away from the first of the month when people get their money.”Schools are closed on Thursday in Boston, Worcester and Springfield, but Lynn Public Schools were planning to go ahead with classes as of Wednesday afternoon. Nevertheless, Superintendent Dr. Catherine Latham urged students to dress warmly in hats, mittens and coats, and Latham announced that all school buildings would be open as soon as faculty and staff arrived, so that students could come inside from the cold.Byrne said the shelter has extended its hours so that it is open and staffed for all but between the hours of 10 a.m. and noon. This change has been in effect since Nov. 17, and the times the shelter is closed coincides with some of the time when My Brother’s Table is open and providing services for the homeless.Lynn District Fire Chief Jack Barry reminded residents to check on their neighbors, especially the very young and the elderly who are more susceptible to extreme fluctuations in temperature if they lose heat.He reminded residents to be careful using space heaters. He added that residents should always use them in an area that is relatively open and – most importantly – only plug space heaters directly into a power supply. Do not use extension cords.”Extension cords will heat up and overheat and could ignite combustibles around them due to the energy that the space heaters draw,” Barry said.He also advised residents to keep water flowing in pipes – even just a trickle – to prevent pipes from freezing.The National Weather Service reported the Berkshires and Worcester hills will have overnight lows Wednesday between 5 and 15 degrees below zero, with winds chills as low as minus 30. In other areas, lows are forecast between 5 degrees above to 5 degrees below zero and wind chills around 20 below.