mail shea@uwp.edu, ljanders@facstaff.wisc.edu


Jim -

I was asked by Lyle Anderson of the State Climatology Office 
to respond to your email messages concerning your analyses of 
the temperature record at Kenosha.  I have looked at your 
discussion and went back to the daily records, then produced a 
time series of the annual temperature.  I arrived at similar 
statistics as you indicated.

Yes, the annual temperature signal for Kenosha is very similar to 
that exhibited by long-term temperature records taken at other 
stations in Wisconsin.  I took a look at my spreadsheets of the 
long-term monthly temperature records for selected stations in 
southeastern Wisconsin, south central Wisconsin and east central 
Wisconsin. In my search I attempted to look for various stations 
that were not just the Milwaukee and Madison city records.  I also 
took a look at the divisional average temperatures for each of 
these climatological divisions (9 divisions across the state).  
All annual records appeared to exhibit similar trends as you 
noted.  Specifically, several warm years in the early 1950s, 
followed by a drop to the early 1960s, then a marked increase 
in the annual temperature just before 1990, followed by a drop 
in the mid 1990s to a relatively cold 1996, with a rapid increase 
by 1998.  In fact, the statewide annual average temperature record 
also has some similar variations, with the year 1996 being the 
second coldest year in Wisconsin since 1891, while 1998 was the 
second warmest for that 108 year interval. 

I am curious as to what you were expecting to find in your record.  
If you were thinking that some decisive long-term trend in 
temperature would appear, then I am afraid that you will be 
disappointed, since this trend is not borne out.  The observed 
temperature record for Kenosha, southeastern Wisconsin or the 
whole state is more complex, depending upon many factors. 

While these annual temperature records may appear surprising, I 
would suggest that you look not just at the annual averages, which 
may be too course a time averaging interval.  (Specifically, a 
cold winter may be sufficiently cold or persistent or a 
combination of both, to completely compensate for a short, hot 
summer.) You may want to consider the meteorological seasons, such 
as summer (June, July and August), or winter (December, January, 
February) for further analysis.  Here, you may find that some 
summers in the 1950s were quite warm - and dry.  The summer of 
1988 was a hot, dry summer.  The winter of 1997-98 was very warm 
also, making 1998 appear to be "hot".

Regardless, I am happy that you contacted us about your 
observations.  I hope that my comments here may help alleviate 
your concern.  If you have any other questions or comments, please 
feel free to contact me.

Edward J. Hopkins, Ph.D.
Meteorologist