Monday, September 2, 2013

The Meteorology of Husky Stadium


Pride swelled among the University of Washington community with the opening of the massively refurbished and modernized Husky Football stadium, with the win over Boise State providing the icing on the cake.

But knowing the meteorology of the stadium can only enhance the enjoyment of this new sports palace, so let's consider a few relevant weather facts.

A maps sets the meteorological scene (see below).   The stadium is in northeast Seattle and is open to the east-southeast, with the water of Portage Bay only a few hundred feet away.


Thus, the two very high stands of the stadium act as barriers to winds from the south and north.   Winds right into the stadium from the east-southeast are VERY rare and are pretty much  limited to heat wave/easterly downslope situations.   The stormiest, windiest, wettest and most unpleasant fall weather is from the south to southwest and thus the south stand should effectively block the winds from that direction for mcuh of the interior of the stadium.  Under those conditions, those in the south stands will be quite dry, even during rainy periods.  In contrast, the lower to middle portions of the north stand will be wet, although the winds should be modest for southerly flow.  For southwesterly or westerly winds, which can happen after frontal passage, the north stand could be blustery.   So get a seat on the south stand if you want to be safe.

Blockage of the prevailing strongest winds by the south stand suggest that strong wind is rarely an critical element in game play during the worst weather.  But that does not mean unimportant.  Above the  center of the field and on the sides, there could well be turbulent eddies coming off the edges and tops of the structures.  In fact, such eddies have been suggested by players in the past:

"In Husky Stadium the wind swirls a lot, and it changes direction as you go up in the stadium. You try to gauge the wind from where you're actually kicking, but once you've kicked, you can watch the ball actually change directions as it's going through the air. The hardest thing to do is just figure out what's going on."  - punter Derk McLaughlin.   

Now the folks you have to feel sorry for are the students who were moved from central, near-field locations to new stands on the southeast side of the field (see, white area on the 3D graphic).  They will not only get minimal shielding by the south stand, but if south/southwest winds blow, the gusts will be strengthened as the wind moves around the eastern edge of the south stands.  The higher-priced northeast stands will be be fairly wet, but the building structure is high enough to protect them from much of the wind.


Strangely enough, Husky stadium is in a weak rain shadow during fall storms:  the rain shadow of Capitol Hill (see Seattle terrain map).  For southerly or southwesterly winds, the direction normally


associated with fall storms, air rises on Cap Hill, providing more rain, and descends to the north of Cap Hill, where the stadium is located, reducing precipitation amounts.   Several years ago, Mark Albright, then state climatologist,  maintained a very dense cooperative rain gauge network.   The result was that he documented the Cap Hill rain shadow, which reduced precipitation by 10-20%. To show this, here is a precipitation map for September 1986-May 1987 made possible by a very dense precipitation network that Mark Albright ran for years.   Look closely and you will see that Cap Hill got about 40 inches while down in Husky gulch there was around 35 inches, FIVE INCHES LESS!  Pretty amazing isn't it.



During the warm, early season games, the north stands will have the advantage of much more sun (see image below from old stadium), clearly an advantage on nice days.


The nearby water and natural marsh areas near the stadium generally moderate the temperatures in the stadium...they are usually cooler that downtown and even nearby University District locations (I can confirm this....I have run past the stadium three times a week for years).

Before the construction there were weather  sensors at the stadium (id: SEAWA) that was part of the KING-5/Weatherbug network.  Hopefully, a new weather station will be installed on the new facility.

3 comments:

Michael Brandt said...

Cliff, your comments about the stadium winds are interesting. I can't speak too much about winds in the seating areas but as a member of the UW track team back in the 1960's I can say that it was not uncommon on Spring and Fall windy days for the geometry of the structure to produce a headwind for an entire circuit of the track; a real downer for a quarter mile sprinter!
Thanks, Michael Brandt

Howard said...

I enjoyed reading your report and analysis. The rain shadow effect was new to me. I must comment on the statement about sitting in the sun on the north side being a good thing. Until you have baked (or should I say broiled) in your seat on the lower north upper deck for 3 hours a game in September, you have not experienced the worst!can cover up against the rain and cold of later months but September was torture!

John McBride said...

The rain and sunlight information is informative to have documented but I've been going to the stadium since 1959, then as a student in the early '70s and steadily since 1983. My anecdotal opinion would have been that the stadium was blocked.

By the way, I don't want to rain on the U's parade, but regardless of the new stadium hype, from my perspective it's changed, and different, and new, but not better.

The student section is blocked from participating in a leading way it formerly had and the band is harder to hear. The new stadium has a commercial, decidely not college feel to it.

Ya, the world has changed, I get that. But change isn't always progress.

Cliff, I understand we could be in for severe weather Thursday - Friday.

What's your input?

Thanks!
.