Weather Blog

Heat and hydros go hand-in-hand

Heat and hydros go hand-in-hand

We already know Seattle's weather is a bit quirky. True fact: July 4th is the wettest day in July.

But on the other hand, did you know that traditionally, the day we hold the hydro races at Seafair have coincidentally been among the hottest in Seattle?

As the temperatures are expected to climb near, or perhaps above 90 on hydro Sunday, it turns out a 90 degree hydro day would barely be in the top three warmest.

With the help of this great hyrdro racing site Lesliefield.com, I was able to track down the dates of each hydro race back to 1951 (since the date "floats" each year -- and some years they were held the first Sunday in August; other years it's been the second) and the results were somewhat surprising.

In 1981, it was a sweltering 99 degrees the day the "Sea Galley APBA Gold Cup" was held. (Surprise! Miss Budweiser won.) At the time, it was tied for the hottest day in Sea-Tac history. The date it was tied with? August 9, 1960. That was two days *after* the races were held that year, but the day of the races in 1960 it was "much" cooler: 87 (and 98 on that day in between.)

The races in 1971 and '72 were also quite the swelter with high temperatures of 90 and 91, respectively. There are several other dates -- including three years ago in 2009 (89) -- that were well into the 80s. In fact, 12 of the 61 years had temps over 85.

On the other hand? There were eight days with highs in the 60s and 10 days with measurable rain, topped off by the 0.35" in 1995. (Still remember that day. We had guests in from out of town that year. Not surprisingly, they've never been back to Seattle.)

But combine all the years, and the average high temperature on hydro race day is 77.3 degrees -- exactly the normal average high for this time of year, which I guess makes sense. And 10 rainy days out of 61 years comes out to about a 16 percent chance of rain -- pretty close on par with what we expect this time of year.

This year's race should boost that high temperature average and well have to see how high up the chart we end up. Forecasts currently would put us No. 3 or 4 but No. 2 is not out of the question!

Hottest SeaFair Days:

1981: 99
1972: 91
1971: 90
2009: 89
1952: 88
1960: 87
1997: 87
1980: 87
1977: 86
2006: 86
1990: 85
1989: 85
Average high temp (1951-2011): 77.4
10 days with rain out of 61.
Wettest day 0.35" in 1995