Bad Weather Delays SpaceX Cargo Mission to Space Station

SpaceX's Falcon 9 rocket and Dragon cargo capsule stand poised to launch toward the International Space Station on July 24, 2019. The launch attempt was nixed because of bad weather.
SpaceX's Falcon 9 rocket and Dragon cargo capsule stand poised to launch toward the International Space Station on July 24, 2019. The launch attempt was nixed because of bad weather. (Image credit: SpaceX)

CAPE CANAVERAL, Fla. — SpaceX’s next cargo mission to the International Space Station (ISS) has been delayed by at least 24 hours due to poor weather conditions.

The company's workhorse Falcon 9 rocket was scheduled to launch a robotic Dragon cargo capsule today (July 24) from Launch Complex 40 here at Cape Canaveral Air Force Station at 6:24 p.m. EDT (2024 GMT).

Both the Falcon 9 and the Dragon have flown before. Indeed, the capsule has two ISS missions under its belt, and will be the first Dragon to launch toward the orbiting lab three times when it finally does lift off.

Related: How SpaceX's Dragon Space Capsule Works (Infographic) 

According to the Air Force's 45th Space Wing Weather Squadron, there was just a 30% chance that Mother Nature would cooperate with today’s launch attempt. Will Ulrich, an official with the Weather Squadron, explained the concerns in a pre-launch press conference this morning. 

"Today’s weather looks terrible," he said. "There’s a pretty unique weather pattern we have in place." 

The direction of wind flow dictates where any showers and thunderstorms will go, he explained. An unusual cold front is currently draped across the southeastern United States and is driving the current steering flow. The cold front is also the reason there’s extra moisture in the area, Ulrich said.

"With an instantaneous window today, either the weather is good or it is not," he told

Anvil clouds and cumulus clouds were a cause for concern. Therefore, weather officials closely monitored lightning, noting that area clouds could hold electrical charge for several hours. This held charge could potentially trigger lightning if a rocket were to pass through those clouds.

In addition to weather concerns at the launch site, the 45th Space Wing also has to monitor conditions downrange where the rocket is heading.

As the countdown progressed, weather conditions at the Cape deteriorated. Due to the instantaneous launch window, crews had to stand down from today’s attempt. The next launch opportunity opens tomorrow (July 25), but conditions are expected to be similar on that day, with just a 30% chance of good weather, according to Weather Squadron officials.

If the Falcon 9 cannot get off the ground tomorrow, the next attempt could come as late as Aug. 1, because of the position of the space station on orbit as well as station traffic, NASA officials have said. But SpaceX and NASA are still working on finalizing backup dates. 

When Dragon does launch, it will carry approximately 5,000 lbs. (2,270 kilograms) of supplies for the station, including 2,500 lbs. (1,134 kg) of scientific research to support dozens of experiments aboard the ISS. 

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Amy Thompson
Contributing Writer

Amy Thompson is a Florida-based space and science journalist, who joined as a contributing writer in 2015. She's passionate about all things space and is a huge science and science-fiction geek. Star Wars is her favorite fandom, with that sassy little droid, R2D2 being her favorite. She studied science at the University of Florida, earning a degree in microbiology. Her work has also been published in Newsweek, VICE, Smithsonian, and many more. Now she chases rockets, writing about launches, commercial space, space station science, and everything in between.