Houston Astros already lead Seattle Mariners… in retractable roof usage

There's been countless stories already about the ALDS matchups between the Seattle Mariners and Houston Astros on the field, but what about the fields themselves?

HOUSTON – The matchup this week between the Houston Astros and Seattle Mariners in the American League Division Series isn't just between AL West foes, it's between the only two remaining teams in the playoffs whose stadiums feature a retractable roof.

There have been countless stories already about the matchups on the field, but what about the fields themselves?

Houston: Why does our roof retract?

It might surprise you to find out Houston far and away leads Seattle in the use of their stadium's retractable roof, despite Houston having much more of a summery reputation than Seattle, which in some corners is known as "Rain City USA."

But it's that sultry Houston summer where that roof comes in handy. Minute Maid Park can become a fully-enclosed dome when the roof is extended -- a welcome, air-conditioned relief from what typically feels like a triple-digit sweatbox in the summer months.


These days, their roof remains closed for much of the season during games, only opening a handful of times in April and September when the weather is somewhat bearable. This season, the Astros played just three games with the roof open -- two in April and Sept. 27. In 2021, the roof was only open seven times.

It was sunnier times when the stadium opened at the start of the century. During Minute Maid Park's inaugural season in 2000, the roof was open 30 times and moved to either open or close during another 32 games. But with the novelty wearing off over the years, the roof remains closed nearly all the time. Perhaps it's for good reason, the Astros have a .507 winning percentage with the roof open versus a .561 winning percentage with the roof closed.

The Astros will continue the domed trend this week despite slightly cooler October weather, as both Games 1 and 2 of the ALDS will be played with the roof closed, according to an Astros spokesperson. The decision appears weather-independent, but it may be a fortuitous decision for Tuesday's game anyway.


"We've got some isolated showers out there today, which is a good reason to keep the roof at the Juice Box closed," said FOX Weather senior digital content producer and meteorologist Aaron Barker, who is based in Houston. "Otherwise, we're looking for a decent mix of sun and clouds along with warm temperatures this afternoon. It'll be in the upper 80s outside Minute Maid at first pitch with temps dropping only slightly by the end of the game."

Seattle: Why do we have a roof?

The Mariners spent their first few decades playing in the concrete palace known as the Kingdome, relegating fans inside during many a glorious summer evening in the Pacific Northwest when rainfall is rare and average highs are in the mid- to upper 70s. So you can imagine the excitement when plans came together for a retractable roof stadium that would allow outdoor baseball.

The conventional wisdom was it still rained enough in Seattle -- especially on the fringes of summer -- to warrant the need for a roof. Seattle's fan base covers a large geographic footprint, so team owners wanted to assure fans if they made a several-hour trek to see a game that there would be no rainouts, even if the forecast called for showers.


But likely contrary to popular belief, their roof spends most of the year collecting dust. The Mariners only average about 11 of their 81 home games per year under a closed roof with a handful of additional dates needing roof closure during the game -- the least frequently-used retractable roof in the major leagues.

That means about 70 home games a year are in the full elements. Unlike Minute Maid Park, T-Mobile Park's roof does not enclose the park, but rather it acts like a large umbrella. Thus, the roof has no significant effect on temperatures inside the park and is only used to keep dry, not cool or warm.

With the forecast calling for dry and pleasant conditions in Seattle over the weekend when the series shifts back to the Northwest, you can be near certain T-Mobile's roof will be open – boding well for the home team. The Mariners have a .526 winning percentage with the roof open but .512 when the roof is closed.