A SpaceX Dragon cargo capsule on final approach to the International Space Station. The company planned to launch its sixth operational resupply flight Monday to deliver nearly 4,400 pounds of supplies and equipment to the lab complex. SpaceX

Last Updated Apr 13, 2015 5:07 PM EDT

Electrically active anvil clouds approaching the Cape Canaveral Air Force Station Monday forced SpaceX to order a 24-hour delay for launch of a Falcon 9 rocket carrying a Dragon cargo ship loaded with nearly 4,400 pounds of scientific equipment, spare parts, food and other crew supplies -- including an espresso machine -- to the International Space Station.

Liftoff from complex 41, originally planned for 4:33 p.m. EDT (GMT-4), was tentatively reset for 4:10 p.m. Tuesday. But forecasters expect more of the same summer weather, giving SpaceX just a 50-50 chance of acceptable conditions.

Because the propellant demands of a station flight are slightly less than for a commercial satellite launching, SpaceX will make another attempt to land the rocket's first stage on a remotely controlled barge-like platform stationed a few hundred miles east of Jacksonville, Fla.

Earlier landing attempts were only partially successful due to stormy weather and problems with stabilizing fins needed to help control the descent.

But this time around, SpaceX managers are hoping for better results, thanks to improvements in the rocket's descent system and upgrades to the landing ship, named "Just Read The Instructions." A senior SpaceX manager put the odds of success at up to 80 percent, but company founder Elon Musk said that's the expectation by the end of the year.

"Odds of rocket landing successfully today are still less than 50 percent," Musk tweeted Monday. "The 80 percent figure by end of year is only bcs (because) many launches ahead."

Whenever it takes off, the flight plan calls for the Falcon's first stage engines to burn for a little under three minutes to boost the rocket out of the dense lower atmosphere. At that point, the Falcon's single-engine second stage will take over the push to orbit, putting the Dragon cargo capsule into an initially elliptical orbit to set up a three-day rendezvous with the space station.

While the second stage continues the climb to orbit, the first stage will flip around and re-enter the atmosphere, using three rocket firings to reduce its velocity and bring the booster down on the landing barge.If all goes well, the Dragon will reach the space station early Friday, pulling up to within about 30 feet and then standing by while Italian astronaut Samantha Cristoforetti, representing the European Space Agency, locks on with the station's robot arm. Ground controllers then will remotely operate the arm to pull the capsule in for berthing at the Earth-facing port of the forward Harmony module.

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SpaceX ship carrying two tons of cargo to ISS delayed