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Average 100F Days In Houston

Posted: Tue Aug 17, 2010 10:21 pm
by Ptarmigan
So far this year, we have seen two 100F days. Wonder what is the average for Houston to see 100F days?

1921-2009 (Houston WB and KIAH)
Mean
3 Days

Median
1 Day

Standard Deviation
5.412528


1921-1969 Houston WB
Mean
1.836735 Days

Median
0 Day

Standard Deviation
2.544168


1970-2009 (KIAH)
Mean
4.425 Days

Median
1 Day

Standard Deviation
7.372463


Top 5 Most 100F Days At Houston WB
1951/1962 8 Days
1924/1930/1969 7 Days
1925 6 Days
1944/1954 5 Days
1927/1932/1948 4 Days

Top 5 Most 100F Days At KIAH
1980 32 Days
1998 24 Days
2000 20 Days
2009 17 Days
1993 14 Days

Most likely it is due to Houston building up and also asphalt runways nearby at the airport.

Years Where 100F Days Were No Recorded
Houston WB
1922-23
1926
1928-29
1931
1933
1936
1938
1940-43
1946
1949-50
1952
1955-56
1959
1961
1965-68

KIAH
1972-75
1979
1981-84
1989
1991-92
1996-97
wxman57 wrote:I believe that we're seeing more 100F days lately because the thermometer exposure is different from the "old day". With lots more concrete around the city, there's a heat island effect that wasn't in existence much of the last century (until the 1970s). There are just a lot more heat sources than there were in the first half of last century.

In addition, I've seen studies that suggest the change to a new material for instrument shelters may have contributed to most of the temperature rise last century attributed to global warming.
WXMan57 raises a very good point from another topic I created about 100F days and major hurricane landfalls.

Re: Average 100F Days In Houston

Posted: Thu Sep 02, 2010 8:33 pm
by txagwxman
Min Avg Temp
August 2010 2009 2008 2007 2006
Houston IAH 77.9 76.1 75.3 76.4 75.7
Conroe 73.8 72.8 73.1 72.8 71.6
Hooks Airport 74.4 72.9 73.1 75.3 75.2
Sugar Land 75.4 74.3 75.6 76.1 74.5
Houston Hobby 77 76.9 75.8 78 76.6
Delta for IAH 2.75 1.875 0.9 0.85 1.225


Here is a diagram of min temps for August for surround areas since 2006.

Notice that IAH delta is 1-1.5F warmer now vs 4 years ago.