Why Jan. 21 is most intriguing (and controversial) day for Detroit weather records

A record low controversy (at least in my eyes)

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DETROIT – Strictly from a historical standpoint, Jan. 21 is a most intriguing day for Detroit weather records.

You see, on Jan. 21 in 1984, we set a record low of -21 degrees (-29 degrees Celsius), which officially stands as the coldest recorded temperature in Detroit weather history. But is it really?

Back to the books?

Let me explain. Our National Weather Service office has the old books that the daily weather statistics were hand-recorded in, and Detroit weather records date back to 1870. At least they used to. Back when the NWS office was located at Metro Airport, they had all of the old record books. But when the office moved to its current office in White Lake, the oldest book -- 1870-1873, somehow got lost (as a historian, words cannot adequately describe my distress when I heard about this). So, as things stand today, we only have the records books starting with 1874.

That 1870-1873 book had a record low temperature of -24 degrees (-31 degrees Celsius) on December 22nd, 1872 and, up until the time that book was lost, the National Climatic Data Center (now called the National Center for Environmental Information) certified that temperature as Detroit’s lowest recorded temperature.

But once that book was lost, all records set from 1870 to 1873 were disqualified. I truly don’t understand this -- we HAD the data at one time. Sure, the original records are now missing, but we still have THE DATA. At the start of my career, -24 degrees was officially Detroit’s coldest temperature. But it’s not now.

One thing I’m going to do once this pandemic is over is head over to the Burton collection at the Detroit Public Library’s main downtown branch, and look at the old newspapers from 1870 to 1873. If the papers reported the previous days’ weather stats, then perhaps this documentation would be enough to re-certify the temperature and precipitation records set in those years.

I maintain an Excel spreadsheet with all of Detroit’s weather records, including some oddball records not typically kept. My spreadsheet still has the 1870-1873 records, as I still recognize them, so I know which days to check the papers. Stay tuned…I want to fix this problem!

About the Author:

Local 4 meteorologist Paul Gross was born in Detroit and has spent his entire life and career right here in southeast Michigan. Paul has researched, written and produced eight half-hour documentaries for WDIV, as well as many science, historical and environmental stories.