Peoria Temperature Records

One indicator of the climate that I feel is overlooked is the record high and low temperature records.  If we were seeing an "unprecedented" increase in global temperatures, then wouldn't we expect to see numerous record high temperatures also?  Conversely, if global cooling were happening, then we might expect to see a higher number of record lows.  My own personal curiosity led me to examine the record highs and lows from Peoria, Illinois. 

Like many US stations, records for Peoria date back to 1884.  This means that this city is in its 125th year of collecting temperature data.  While the first and last decades have incomplete records, an average year would produce 2.9 record highs and 2.9 record lows.  This gives a weighted average for each decade of 29 record highs and 29 record lows. 

The record high data below (Graph 1) shows a huge spike of high temperatures in the 1930's with above average numbers in the 1890's and 1980's.  The 89 record high temperatures in the 1930's represent a 307% increase above the weighted average.   

While many of the record highs come from the summer of 1936, almost every year in this decade produced an above average number of record highs.  The breakdown of each year is seen in Table 1.  The years 1930, 34, 36, and 39 stand out as some of the warmest according to the high temperature records.

Table 1:

Year

Number of

Record Highs

1930

16

1931

5

1932

3

1933

9

1934

15

1935

1

1936

21

1937

3

1938

5

1939

11

Some have claimed that 1998 was the warmest year on record.  Yet, in Peoria, it produced only three record highs all occurred during the colder months of January, November, and December.  As seen above, both 1934 and 1936 produced many more records.

Examining the low temperature records below shows the biggest spike in the 1970's with a second smaller peak in the 1910's.

  

The latest decade currently has a total of 20 record highs and 12 record lows.  This is a fairly unspectacular amount of both.

In conclusion, this data seemingly confirms what many of us already knew the warmest decade was the 1930's and the coldest decade was the 1970's.  Further, the current decade is fairly average and not of "unprecedented" warmth. 

 

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