The Firefly Aerospace rocket’s return to flight will wait a bit longer at Vandenberg Space Force Base as a rain storm aims for the Central Coast at the start of the week, but a bigger rocket remains on track for its departure at the week’s end.

On Friday, Firefly officials said they called off plans for an early Monday morning liftoff from Space Launch Complex-2 at the base. 

“We have received a weather update surrounding the storms off the west coast of the U.S. that is causing a delay to our launch window,” Firefly officials said on Twitter.

A chance of rain remains in the forecast for Sunday night and Monday for North County with lesser chances for areas to the south, according to the National Weather Service. 

Firefly representatives were working with Vandenberg officials to reschedule the launch.

“New launch window is now no earlier than September 29th. Alpha stands ready to launch.”

The Firefly team counted down toward liftoff on Sept. 11 but a helium pressure problem kept the 95-foot-tall boost on the ground. 

Plans for a second try on Sept. 12 were scrubbed due to windy conditions as the Central Coast dealt with remnants of Tropical Storm Kay. 

Meanwhile, a different rocket, the United Launch Alliance Delta IV Heavy, continues to march toward its Sept. 24 liftoff for a mission to carry a National Reconnaissance Office payload. 

The mission involving classified cargo has been dubbed NROL-91.

On Friday, officials announced the Delta IV Heavy departure from Space Launch Complex-6, originally built for the West Coast space shuttle program, will aim for 2:53 p.m. 

While the launch window remains top secret due to the cargo headed to space, the rocket’s flight won’t occur any later than 4:12 p.m., officials have said. 

NROL-91 will be the 10th Delta IV from Vandenberg, and the fifth and final heavy variant from Vandenberg.

Delta IV Heavy employs three core boosters strapped side by side to carry some of the nation’s heftiest payloads into space. 

Noozhawk North County editor Janene Scully can be reached at jscully@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.