The alerts act as warnings for those planning to be outside.
In some cases they also allow for activation of emergency warming shelters for anyone in need.
The following counties have issued Code Blue alerts:
Philadelphia 7 p.m. Friday - 7 a.m. Sunday
Montgomery County, Pa. 8 p.m. Friday - 8 a.m. Saturday
Burlington County, N.J. 7 p.m. Friday - 7 a.m. Saturday
Cumberland County, N.J. All day Friday - 6 a.m. Saturday
Check local websites for more details on Code Blue alerts in your area.
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