Two cousins aged 14 and 15 have been reported missing from their home in Newton Aycliffe.
Thomas and Kieran Miller have not been seen since Sunday.
The police say they are concerned because of the age of the boys.
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Storm Doris is set to bring wet, windy and wintry weather to the region.
Severe weather warnings have been put in place for much of the UK on Thursday,with the North urged to "be prepared".
Boro will face either Man City or Huddersfield at the Riverside.