The United States spent the second week of October dismantling its own temperature records, in numbers that are easier to state than to absorb.
According to the National Climatic Data Center, more than 600 daily high records were tied or broken in the week to 14 October, primarily across the central and eastern states. Another 700 daily warm-low records were tied or broken as well, so there was little relief when the sun went down. The figures were reported by Rob Shackelford for weather.com.
St Louis came within a degree of its all-time October heat record, reaching 93 degrees Fahrenheit at Lambert International Airport. The all-time mark is 94 degrees, set in 1953. The 93 degrees did, however, shatter a daily record that had been in place for over 100 years, dating back to 1899.
The Twin Cities had back-to-back record days, reaching 90 degrees on 10 and 11 October, more than 20 degrees above the historical average. Denver has seen its longest streak of 80-plus-degree days in October since record-keeping began.
Downtown Los Angeles has had five days above 100 degrees so far this month, which has never happened there in October. The previous record was four such days, in October 1958 and again in 1971. This year's five were consecutive, from 2 to 6 October, which ties the third-longest stretch of consecutive 100-degree days on the city's books. It has also been downtown Los Angeles's hottest 1 June to 4 October of all time.
The week is not an isolated blip. NOAA reports that January to September was the warmest such period on record for the contiguous United States in 132 years of data, driven partly by the hottest September ever recorded nationally.
Eight states, among them Oklahoma, Missouri, Kansas, Texas and Illinois, posted their warmest Septembers on record, according to the National Centers for Environmental Information, with some beating marks that dated back to the Dust Bowl era of the 1930s.
Much of that warmth came from unusually warm overnight lows rather than scorching daytime highs. An estimated 80 million Americans experienced their warmest September nights on record. The country is on pace for its hottest year ever measured.
This newspaper wishes to draw attention to a feature of the week that the meteorological coverage has passed over, which is that a daily temperature record is not weather. It is a holding.
Each weather station carries a fixed inventory of exactly 365 daily high records and 365 daily warm lows, acquired at a rate of one a day and replaced only when superseded. In the week to 14 October the United States wrote off more than 1,300 of them.
The useful life of the asset is clearly shortening. The daily record retired in St Louis had been on the books since 1899, giving it a service life of 127 years. Our analysts regard that as an unusually durable holding and have begun amortising more recent ones over considerably shorter periods.
The Dust Bowl marks in the warmest-September states have now been superseded, which in accounting terms makes them fully written down. They retain a historical value, in the sense that somebody wrote them in a book, but they can no longer be presented as current.
The St Louis all-time October record of 94 degrees, set in 1953, survives by a single degree and should in our view be reclassified as an asset held for sale.
The Department of Unnecessary Research has calculated the depreciation schedule and finds the position straightforward. The record set at Lambert International Airport in 1899 lasted 127 years. Its replacement is expected to last until next October.