James Dean

FLORIDA TODAY

Update, 3:20 p.m. ET:

SpaceX has scrubbed today's launch attempt due to a concern identified during pre-flight checks.

An advisory issued by the company shows Tuesday as the next available launch date.

The advisory said the vehicle and its payload were in good condition. Teams will use the extra time to further prepare both for Tuesday's attempt.

Check back for updates.

Update, 11:20 a.m. Sunday:

Showers and thunderstorms are expected to be a factor again during tonight's third attempt to launch a Falcon 9 rocket and six Orbcomm satellites from Cape Canaveral Air Force Station.

Air Force meteorologists expect a 20 percent chance of acceptable weather, but a longer launch window could help the cause.

Launch is targeted for 5:30 p.m., the opening of a window that closes at 8:08 p.m. The previous windows have been under an hour.

Cumulus clouds, lightning, anvil clouds and high electric fields within the window are the primary weather concerns, according to the 45th Weather Squadron.

"Conditions will gradually improve near sunset and through the evening hours," notes today's official forecast.

Similar weather is expected through mid-week.

Thunderstorms and lightning strikes thwarted Saturday's second launch attempt.

"Both Falcon 9 and the ORBCOMM satellites are safe," Orbcomm reported afterward.

Technical problems with the Falcon 9 scrubbed Friday's first countdown.

SpaceX is launching the first of two missions planned this year for Orbcomm Inc. Today's launch aims to deploy the first six of 17 Orbcomm Generation 2 satellites in low Earth orbit that will form the company's next-generation network for machine-to-machine communications.

If the countdown stays on track, fueling of the 224-foot Falcon 9 with rocket-grade kerosene and liquid oxygen should start just under four hours before the targeted liftoff from Launch Complex 40.

We'll resume live countdown coverage here at 4:30 p.m.

Original story:

CAPE CANAVERAL – The Space Coast's quietest rocket countdown in recent memory ended Saturday with the same result as a more public production on Friday: Scrub.

Weather prevented SpaceX from launching a Falcon 9 rocket and six commercial satellites from Cape Canaveral Air Force Station, one day after technical problems kept the mission grounded.

Orbcomm, which operates the satellites SpaceX is boosting into space, said late Saturday night that a 5:30 p.m. launch opportunity had been confirmed for this evening.

On Saturday, SpaceX never explained the cause of fluctuating rocket tank pressures that halted Friday's countdown, or what it had done to fix the problem.

RELATED: FLORIDA TODAY will have live coverage this afternoon.

It provided no Webcast, as it had Friday, and no online updates or tweets throughout the launch window on the countdown's status, leaving media and other observers with little real-time information.

Launches of U.S spy satellites typically are more transparent, but SpaceX was not obliged to include the public in a commercial launch for Orbcomm Inc.

Orbcomm, a New Jersey-based provider of machine-to-machine communications, was the first to confirm the launch attempt was a "go" on Saturday morning and again late Saturday for today's attempt.

The company promised to post updates as the launch neared, but never did.

With late afternoon thunderstorms buffeting the Cape, SpaceX moved the liftoff time to the end of the launch window at 6:39 p.m. – evident on a countdown clock at nearby Kennedy Space Center.

But the weather never cleared. SpaceX did not discuss the rocket's performance.

The Eastern Range was believed to be about to start scheduled maintenance that could limit launch opportunities for at least a week.

If for some reason today's launch attempt was waved off, it's not clear where the launch stands.

The Air Force's 45th Space Wing, which operates the range, has not responded to questions.

Once planned in April, the mission to launch the first six of 17 satellites for Orbcomm has suffered multiple delays due to issues with the rocket, spacecraft and range.

If SpaceX can get this mission launched, it hopes to launch another commercial satellite from Cape Canaveral in mid-July.