Decades of 100s, but just how many days?

CREDIT: BaytownBill on Click2Pins

HOUSTON – I love my viewers and data, so this recent email was sent to the right person:

“You may have sent this recently, but has anyone put together a chart showing the number of 100+ degree days each decade since 1960?”

-- Joe

That’s an interesting question and a pretty easy one to answer actually, but there are different ways to look at the answers! I used June to September maximum temperature data from Hobby Airport for the 1960s and Bush/IAH for the rest of the decades. Speaking of which, let’s first break this down by decades:

How many summers in each decade had 100°+ temperatures? At least five per decade!

1960s: Five summers (1962, 63, 64, 65, 69)

1970s: Five summers (1970, 71, 76, 77, 78)

1980s: Five summers (1980, 85, 86, 87, 88)

1990s: Six summers (1990, 93, 94, 95, 98, 99)

2000s: 10 summers, all of them

2010s: Nine summers, all but 2014

2020s: Three summers out of four so far

You could surmise from this that climate change is basically doubling the number of 100° summers from five to six each decade to nine to 10. But that would be misleading in a sense and remember Joe’s question was how many days each decade have hit 100°, not just getting to that temperature each summer. For that answer, pull up a chair.

How many days per decade had 100° or higher?

In the 1960s, 1962 had nine days of 100+ while 1963 had one, 1964 had three, 1965 had one and 1969 had four for a total of 18 days.

In the 1970s, 1970 had one day, 1971 had one day, 1976 had one day, 1977 had one day and 1978 had six days for a total of just 10.

In the 1980s, 1980 had 32 days of 100+, 1985 had one, 1986 had eight, 1987 had two and 1988 had four for a total of 47 days!!

So while each of those decades had five summers of triple digits the number of 100° days differed significantly! Let’s keep going:

In the 1990s, 1990 had seven days, 1993 had 14, 1994 had 1, 1995 had nine, 1998 had 24 and 1999 had 10 adding up to 65 days!

In the 2000s, 2000 had 20, 2001 had one, 2002 had one, 2003 had two, 2004 had one, 2006 had one, 2007 had three, 2008 had three and 2009 had 15 bringing in a total of 55 days of 100°+. Every year had 100° but fewer 100° days than the decade before!

In the 2010s, we had 2010 with three, 2011 had 47, 2012 had three, 2013 had six, 2015 had 10, 2016 had seven, 2017 had one, 2018 had five, 2019 had nine and that totaled to 90 days!

This decade we have had eight in 2020, 22 in 2022, and so far 43 this summer! That’s 73 days of triple digits in just four years which beats ALL the other decades except the past one.

Here’s your chart, Joe (add the one today to that 72 down there!):

100° summers and days since 1960

This may be considered cherry-picking, but it’s pretty obvious to me that we are having both hotter summers and hotter days. Stay cool and hydrated, if nothing else!


Email me with questions and comments.

About the Authors:

KPRC 2's chief meteorologist with four decades of experience forecasting Houston's weather.

Amanda Cochran is an Edward R. Murrow award-winning journalist. She specializes in Texas features, consumer and business news and local crime coverage.