You can't just rely on articles. You have to examine all the research.
http://www.gao.gov/new.items/d11800.pdf
According to GAO’s survey of weather forecast offices,
about 42 percent of the active stations in 2010 did not meet one or more of the siting standards. With regard to management requirements, GAO found that the weather forecast offices had generally but not always met the requirements to conduct annual station inspections and to update station records.
...
over 600 stations have been taken offline due to being incorrect.
If numbers appear faulty or if more than nine days are missing from a single month's tally, the whole month is thrown out, according to NCDC documents, and the Center uses a computer program to determine average temperatures at dozens of nearby stations to guess what the temperature would have been for the month at the unknown station.
The USHCN Version 2 Serial Monthly Dataset