July is in the books: TEMPERATURE NUMBERS

My last two posts reinforced how common "cooler" Julys like this month are when we look back as recent as the early 2000s. I also mentioned how the RECENCY EFFECT plays a huge role in our skewed perceptions of July temperatures. The last few years of record heat helped us forget about the other "cool" months of July in our recent weather history.

The final NWS numbers are in. I broke down the July temperatures into two categories: AVERAGE MAX TEMPERATURE and OVERALL AVERAGE TEMPERATURE (MAX and MIN). Where does 2013 fit over the last 30 years? VERY NEAR AVERAGE on both measures. (The prior years--2010,11--are circled in red for reference)

How about the final number of days this July below 80 degrees? Believe it or not, the 11 days below 80 degrees was only slightly above the average average since 1980.

ALMOST HALF OF THE YEARS SINCE 1980 HAD MORE DAYS WITH HIGH TEMPERATURES BELOW 80 DEGREES THAN THIS YEAR

Just for fun, here is the 90 degree scorecard comparing this summer to the last 4 summers.

More "Summer Days in the 70s" Fun

When we think of June and July weather in northern Ohio, high humidity and temperatures in the 80s and 90s are at the top of the list. Cooler summer weather like what we are experiencing now tends to mess with our perceptions of summers past.  Consecutive days in the 70s in late July/early August become very uneasy to swallow.

Weather extremes evoke a very powerful cognitive bias we all have called hard wired into our DNA the "RECENCY EFFECT". This effect gives higher importance to events that have occurred more recently and lesser weight to events further back in time.  The last three summers (2012, 2011 and 2010) have all featured some record heat. These memories are more recent in our minds so we give them more credence than a distant memory of a summer in, say the early 1990s or early 2000s.

Viewer Facebook comments all illustrate this bias perfectly.  Most comment that this summer is so unusual. Most say that don't remember a summer like this in a long time. Yet summers like this one have occurred more often than most of us (myself included) realize. Best of all, we don't have to go that far back in time to find them.

Below is a chart that summarizes ALL of the summers (JUNE and JULY) over the last 30 summers COOLER than this summer. I only averaged the HIGH TEMPERATURES as most of us really don't remember nighttime lows. I listed each year from WARMEST to COOLEST. 

 I'm a stat guy so there is a lot of numbers here. The points that stand out are as follows: 

*  19 OF THE LAST 30 SUMMERS HAVE BEEN JUST AS "COOL" OR COOLER THAN THIS SUMMER. (SEE MY LAST POST)

*   7 SUMMERS (DAYTIME TEMPS) SINCE 2000 (2000, 2001, 2003, 2004, 2006, 2007 and 2009) HAVE BEEN "COOLER" THAN 2013

*  THE MAJORITY OF THESE "COOLER" SUMMERS HAD MORE DAYS IN THE 60s AND 70s THAN THIS SUMMER

* MOST OF THE "COOLER" SUMMERS SINCE 2000 ALL HAD STRETCHES OF "70 DEGREE TEMPS IN JULY" COMPARABLE TO THIS SUMMER

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The moral of the story is we all perceive this summer to be so earth-shatteringly COOL.  Yet even some of our more recent summers contrary to what our memories tell us have been just as cool.

July '13 Temperatures vs. July of 2012

July is coming to a close so I checked the high temperatures nationwide and compared them to July of last summer. First, the last 7 days (July 21 thru 27th)

POLAR OPPOSITES FOR SURE!

Now the last 30 days (June 28th thru July 27th). This takes into account the week of 90s in mid July for Ohio.

2012 WAS STILL A BLAST FURNACE COMPARED TO 2013

How does this summer stack up compared to the most recent summers? Here are the temperatures plotted over the last 30 years for Cleveland. I circled the years that parallel this summer. The most recent summer was not 2009 (as I initially thought) but 2008.

This summer compared to ALL SUMMERS since 1871? This summer circled in red on the right side.

It seems as if we've had "cooler" and "warmer" periods since the 1870s. This summer fits nicely inside our "warmer" trend since the late 1980s.

WILL WE SEE ANOTHER 90 THIS SUMMER? The pattern over the next two weeks will give us insight into the answer of that question.