What is a "Hot Summer," let's get scientific.

Example: How to measure the common perception that Summer 2014 was "A Long, Hot, Dry Summer?"

Period Rated was May 1-October 15, 2014

It can be debated endlessly when to begin claiming "Summer has arrived" in the face of the realities that the Western Washington climate overall is so cool, cloudy and wet. But in 2014, it was easy to set May 1 as the beginning of Summer, because a high temperature of nearly 90 degrees shocked everyone! Officially, it hit 88 in Olympia that day.

Procedure: for this analysis, I will look for hot spells during the period. I will also look at how dry it was by certain measures. And I will compare Olympia to two cities in Oregon that are always hotter and drier than Olympia. Those two cities are Redmond, Oregon in the deserty region of Central Oregon, and Medford, Oregon in the deep valley of the Rogue River in Southwestern Oregon.

First, the absolute upper measures for each city for summer 2014.

Olympia, 96 degrees on August 11, 2014

Redmond, 100 degrees twice, July 16 and July 29, 2014

Medford, 106 degrees on July 28, and 15+ days at 100 or more.

Hottest Days per month 2014, Olympia, measured by taking the four hottest maximum temperatures for the month and averaging them together.

Olympia: May 84 degrees, highest was 88; June 78.75 degrees, highest was 80; July 91.75 degrees, highest was 94; August 92 degrees, highest was 96; September 87.25 degrees, highest was 89.

Hot Spells: for Olympia, the two notable hot spells were these: July 6-16, with an average daily high of 86.2 degrees and highest of 92. And July 26-August 4, with an average daily high of 87.7 degrees and highest of 92.

Dryness: although many people I talked with around the South Sound were exclaiming about what a dry summer it was, the facts were otherwise. Over the May-September timeframe, Olympia measured just over 9 inches of rainfall, which was 1.64 inches above normal for the period. Even the driest month, July, still had over 1/4 inche of rain, and keep in mind that long term climate records specify July as by far the driest month in Olympia.


* CLEAR. National Weather Service (NWS) official rating system of "clear" is a ten-point system, where 0-3 clouds get the "clear" designation. Note that during the very long daytimes of mid-summer, this means that several hours of a day can be worse than "clear," and the day still get a rating of "clear." This is one reason why I also am tracking the "cloudless" category (rated "0" on the NWS scale)..Except I use "Essentially Cloudless Day, 0-1" as my criteria......

"A Cloudless Summer Day" You get up in the morning to bright sunshine, have your morning coffee outside in the sun on the deck. When you go to lunch at noon it's a pleasant, sunny walk to your favorite eatery. When you drive home, it's a long evening of enjoying barbequeing and casual yardwork as the sun gradually sinks into the west. Example: during July 2014 Medford had 21 days that were essentially cloudless (0-1 on the scale)...However, in the Puget Sound, at Sea-Tac Airport* there were only 5 days meeting the criteria.. And, depressingly, there were also seven full days fitting the category of a cloudy day, even in this, the hottest and driest month. .. (* around the Puget Sound, Sea-Tac has the most reliable data set in the cloudiness category)..


Another "Hot Summer" analysis, Summer 2009

Reviewed January 22, 2018