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New "Summer Sanity Index" shows this summer wasn't SO bad...

New "Summer Sanity Index" shows this summer wasn't SO bad...
It's the new Labor Day Tradition around Seattle: Celebrate Bumbershoot, get in those last second Back to School deals, and complain about how lousy the summer weather has been :)

Between last year and this year, it's been a very vocal topic when it comes to the weather: "Man, this summer has been dismal!"

I wrote a story last year documenting that the summer of 2007 wasn't too far off of normal, it just felt cool compared to recent sunny and warmer summers.

Then came this year, which began with the coldest start to June ever.  July was pretty nice and were doing OK into mid-August before the cool rains returned.

But has this summer really been that bad?

Hoping to answer the question once and for all, and to have something to gauge future summers, I've put together what I'm tentatively calling the "Summer Sanity Index" although I am open to suggestions for a better name. (Submit yours in the commenting fields below.)

I went back all the way to 1948 and then for each year, compiled the average high temperature between June 1 and August 31 -- the basic time of summer vacations. (Not counting September since kids are back in school and summer is for all intents and purposes over, even though technically it has three weeks left.) I then rated them on a scale of 0 to 100 -- 50 being an average summer for temperature, 0 being the coldest on record, and 100 being the warmest on record.

To balance this a bit, I then did the same for number of days in that period we had measurable rain -- figuring that is a better gauge than just using aggregate rainfall totals since that could get skewed by a big storm.

(For example, if you had one day of heavy rain but 29 days of sunshine, people would generally accept that is a nicer summer than to have 10 days of lighter rain that added up to less.)

And again, I ranked each year based on 50 being normal, 100 being the least rainy and 0 being the most frequently rainy.  I then averaged the rain and temperature scores together for a final score.

(I wanted to also use number of cloudy days vs. average, but that data is very difficult to find earlier than the mid 1990s -- it's all hard copy buried in some warehouse in D.C.)

So what did I find?

Our recent summers have nothing on 1954, which rates by far the "worst" summer ever. (Yes, I know rain fans, this would be the "best" by your standards, but for ease of writing, we'll go with sunny and warm being what's expected in summer.)  That year was the coldest summer -- with just an average high temperature of 66.23 degrees through the summer. It was also the most frequently rainy with rain on 32 of the 92 days.  It gets a Summer Sanity Index of "0".

The best summer? 1967.  That was the third warmest summer on record -- 77.48 degrees and good for "99" on the index, and just behind the 77.62 degree summer of 1961. But 1967 was the driest with just 6 rainy days that summer to give it a near perfect Summer Sanity Index of 99.5.

So what about this summer? It was just a little below average, scoring 45.5 on the Index. The average temperature was 72.09 degrees, good for a score of 45 compared to the "50" score of 72.60.  We had 20 rainy days, just over the '50' score of 19 average rainy days.

And believe it or not, this past summer actually rated a little worse than 2007, which finished with a score of 46.5. (62 on temperature, but only a 31 on rain).  The 2006 summer, which everyone remembers for being sunny and warm, rated very well, scoring a 70 -- the 10th highest score.

Here is the complete chart:

Year Avg Temp Score # Rainy Days Score Final Score
1967 99 100 99.5
1958 99 77 88
1961 100 69 84.5
2003 84 77 80.5
1987 76 81 78.5
1951 67 85 76
1992 90 62 76
1996 75 73 74
1977 82 65 73.5
2006 75 65 70
1985 77 62 69.5
1965 75 62 68.5
1989 64 69 66.5
1986 67 65 66
1994 74 58 66
1991 64 65 64.5
1998 66 62 64
1979 73 54 63.5
1969 63 62 62.5
1974 62 62 62
2004 81 42 61.5
1988 63 58 61.5
1982 55 65 60
1970 63 54 58.5
1978 75 42 58.5
1984 47 69 58
2002 57 58 57.5
1960 56 54 55
1990 76 31 53.5
1995 59 42 50.5
1972 62 35 48.5
2000 43 50 46.5
2007 62 31 46.5
2005 57 35 46
1952 41 50 45.5
2008 45 46 45.5
1959 45 42 43.5
1976 45 42 43.5
1956 36 50 43
1975 54 31 42.5
1950 58 27 42.5
1973 34 46 40
1981 45 35 40
1966 33 46 39.5
1949 55 23 39
1971 44 31 37.5
1968 55 19 37
1997 53 15 34
1962 42 23 32.5
2001 26 31 28.5
1999 27 27 27
1983 33 19 26
1980 33 19 26
1957 20 31 25.5
1993 31 15 23
1948 36 8 22
1953 18 8 13
1955 13 12 12.5
1964 21 0 10.5
1954 0 0 0